Characteristics of the system-of-interest
The system of interest is discovered situationally, it is agreed upon by a team, there is no algorithm or "typical situations." However, there are heuristics (rules that often work, but not always), which help to find one's system of interest among numerous other systems in various system breakdowns. Yes, the system world is chaotic due to a variety of subjective opinions, but humans tend to organize chaos, to bring structure into it - the chaos symbol looks very structured:
Not everything is bad in the situational identification of the system of interest: there are many signs that will help not to make a mistake when identifying the system of interest.
The word "discovery" here is used not by chance: it is believed that the system of interest exists, it is defined by the type of meta-meta-model, and it only needs to be found/discovered with attention, to define its boundaries - possibly by talking with a large number of various performers playing different roles. We are not bothered by the fact that it concerns the future - in the space-time, this system already exists, only in a future time segment, not right now, which does not prevent describing the system of interest and its role in the supra system even today. The concept of use as a description of the functionality of a "black box" system in a supra system - it is not "invented," not "developed", it is precisely discovered and then documented (it is incorrect to say "fixed," that is to fix the description. This is a hypothesis, it will be refined and corrected! No, the concept of use will continue to be refined and even radically changed throughout the project, and these changes will be documented - changes will be continuously made to these system models as a "black box," there is nothing fixed in it!).
To identify the system of interest (and then deal with all other important systems and "identify our system") - this is to prepare the concept of use, to describe the system of interest as a "black box" incorporated in the supra system that satisfies the interests of external project roles. For example, when you want to entrust some other contractors to create this system in order not to do it yourself, that is, you want to buy a ready-made system and formulate what exactly needs to be purchased, you formulate the concept of use (based on this concept, requirements were previously formulated, often filtering and distorting the information of the concept of use - the same "broken telephone"). Based on the concept of use, you make a purchase (today it is usually not a one-time and final purchase, but implying support - continuous system improvements after its creation, sale, and start of operation).
The system of interest is in the physical world, it is definitely not just a description. If you are making information models, writing texts, creating databases (for example, developing software), drawing diagrams or blueprints, then you usually describe only the system, embodied in the physical world as system documentation, but not as the system itself! Description, even if documented, is not the system of interest! Ask yourself a question: what is described in the document, in the database, in the information models, reflected in the graphics and diagrams, described in the texts? Perhaps the system of interest is described there (or at least its subsystem, or the system of creation: there will be clues as to where to look for the system of interest in the physical world).
If you say, "the system is in the physical world" - and point to an information carrier, people will only believe you if you produce the carrier itself and do not deal with the information on it in essence! The system of interest "a book as a document" is not owned by the writer, but by the printing house or the online store of electronic books. And what about the writer? If this is an engineering project, it would be the embodiment of the world described in the book. The form of the book would not matter here, but the solutions accepted for the arrangement of this world would be important. If it is an educational project, it could be said that with the help of the book, a student's brain area (specialized "wet neural network") is being created as an executor of some practice. This brain area/executor will then manifest as a service provider of thinking (or performing some other practice, considering the involvement not only of the computational part of the brain but also the body and even tools as sensors and effectors) in a certain situation, for which the training of this brain area was intended - and the system of interest here is not just a "brain region," but a "brain region in the moment of its activation" (that is, cognitive manifestation). This brain area in its computational role for practicing can be called "mastery."
This kind of thinking/method resembles projects aimed at changing people's behavior by changing the "brain software" compared to software development projects (this could be called "neuro-linguistic programming," but this term was already taken in the mid-70s of the last century by a specific method of such programming described by John Grinder and Richard Bandler, and thus became unavailable for general use. The changes in neuro-linguistic programming and similar approaches can be seen in the text links "psychopractices of moving along the spectrum of formal thinking", And yes, John Grinder and Richard Bandler used the first-generation systemic approach, one of the prominent system thinkers of this systemic approach helped them - Gregory Bateson. This approach/method is common in modeling changes that people go through (educational projects, promotion of various products and services, psychotherapy, etc.). And remember that the system of interest is defined at the moment of its operation: that is, at the moment when mastery as the corresponding functional part of the brain (implemented today by poorly understood modular parts but fully physical!) will be activated in carrying out work involving the competencies the brain has been taught during training/therapy/programming/coding (yes, the term "coding" was also used!) and so on.
For example, suppose you have a Montessori kindergarten. What is the system of interest? Is it the child? Then what do the parents do for it? Is kindergarten a storage facility for a child, where they keep them while parents work? Heuristic: Montessori kindergarten is an educational process. This means that the system of interest is likely to be some kind of mastery: a functional part of the brain that will be activated in certain life situations, beyond the kindergarten scope. And the kindergarten will only be a provider of education. The exploitation of mastery as a computer/brain part - beyond the kindergarten. Let's say the child is supposed to be taught to be reasonably cautious (not hiding behind parents all the time but also not running into any hellhole available to them), to read poems, not get lost in an unfamiliar environment, to be calm and attentive. This means that the prepared computational part of the brain should not only present a verse reading at the graduation morning event in a familiar environment in the auditorium of the educational institution but confident reciting of the same poem at some festival where the child will be placed on an iron barrel, flashes will come from all sides, parents will be pushed somewhere aside, but the piece of his brain trained in kindergarten will activate, provide calmness, confidence, and recite that same verse. This is the mastery as a result of education, a fully physical object (implemented by constructive parts of the brain). And this will be after a year following graduation, the mastery must be manufactured (engineering terminology! It allows for more precise speech!) so that after a year, the skill does not diminish.
Why write this so detailed? Now you know what the system of interest is (did creative/research/entrepreneurial work, answered the question "what to teach," to which mastery to teach), and only then should you ask questions to the creation system: what practices can create/develop (in our case - educate) such a functional part of the brain? How should this education for the specified type of mastery be structured? You should teach mathematics, carrot growing, and reciting poems in different ways! And then discuss teaching practices and instructional situations, each time questioning how it affects the result: the mastery that will be manifested outside the learning situation. And if a school says, "we teach children to pass the state exams," it may be doubtful that the "state exam passing skill" is exactly the skill the school should be teaching. After discussing what kind of skill it should be, you can discuss the practices of manufacturing this skill: the practices for manufacturing the skill of passing state exams may turn out to be completely different from the practices for manufacturing life skills as a set of applied skills and cognitive skills that the school could produce.
Hair styling is considered in a situation when meeting with the groom, not just any time the owner is in the hair salon, when getting a haircut. Grinding is considered during its use, and all grinding methods are chosen so that everything is fine with this use. The same is true for educating people, and for any other project situations. You must mentally reach the situation of using/exploiting the system of interest.
The system of interest will always have to be discovered, in each project it will be unique, there are no enumerations of "typical solutions" here, only examples can be given - in the hope that these examples will not be taken as "do it this way." Systems thinking sets only a set of concepts that must be carefully considered in your project. It simply guides attention in the project, it does not show how to think. If you find it difficult to make a decision about the system of interest, it means that you do not understand something well about your project, and it would be better for you to think more (as well as gather more information, talk to performers of different roles in the project).
Documentation (paper or electronic) - is not the system of interest, even if it is about a thick stack of project documentation for a high-rise building or even if it is about the source code of a computer program, or even if it is about a scenario of a city festival, or even if it is about some particular competence in someone's head. Perhaps what you describe on this carrier is the system of interest. You may be describing not even the system of interest, but a system in the environment of the system of interest, or a subsystem of the system of interest, or a system of creation. The main thing here - do not confuse systems and descriptions (even if the descriptions are given to us as documentation). The system of interest - this is not a description! The system of interest is most often - the embodiment of what is described!
The system of interest - is what does (that is, it independently changes itself, and does not "influence what someone else changes") the project team. If the team creates a description based on which a system will be made later - this is direct world change planning. This is not convincing someone to change their system, not "analyst recommendations," who usually do not have the authority to implement their recommendations even for the system their team is working on. The team has some authority regarding the system of interest, regarding other systems (environmental systems, including the supra system, systems in the creation chain) the team's power is severely limited.
The system of interest - is what the team ultimately (after the system is fully made and starts successful operation) gets paid for. If the team makes an information model of a bicycle, then in the end, the consumer will pay for a bicycle. Here is the system of interest - the bicycle, the money is specifically for it - the information model of the bicycle is just the bicycle description (even if it is a document, that is, a description on a carrier). But if the team makes an aluminum frame for the bicycle, and this frame is sold only as a bicycle, then even the frame will not be a well-chosen system of interest. It will be a subsystem of the system of interest. However, the airplane engine - is a good candidate for systems of interest. The engine can usually be supplied to be included in various airplane models, engine manufacturers work as part of independent, more or less autonomous enterprises, so the engine is a good candidate. But Rolls-Royce does not sell airplane engines to aircraft manufacturers but sells engine operating hours, so even here are variations: the engine is inherently linked to its maintenance systems, and the engine can only be a subsystem.
The system of interest often crosses the enterprise boundary, goes through its "delivery." Subsystems usually do not cross the enterprise boundary by themselves, only in the assembly as part of the system of interest. And remember that different companies/groups/project teams may have different understandings of what the system of interest is, what its boundaries are, what its level is in the system breakdown, and even what kind of system breakdown exists. Suppliers of airplane engines consider the engine the system of interest. But for an airline manufacturer, the engine is a custom-ordered subsystem.
The system of interest usually has a concept of use, a system concept, architecture, engineering justification. If it is confused with systems in the creation chain, then usually these terms will not be present: in organizations (enterprises, departments, project working groups) as a system, other words are used - "strategy," "key performance indicators," etc.
If you have discovered that a certain process is the system of interest, think two or three times which system actually performs this behavior. If it’s rest, your system of interest is most likely the one that is resting (and has rested). If it’s life - it’s a living agent, lived and experiencing no regrets about the process of living. If it’s dance (remember the ambiguity of the word! Here it is a performance, dancing), then it may be the spectator who viewed this dance, and sometimes even the dancer-agent, who is also "the spectator of themselves," these are all role considerations when one agent can play two roles during a performance - both dancer and spectator.
If you have some "work process," then most likely you are interested in the result: the system of interest is not a haircut::process but a hairstyle (haircut is one of the processes of getting a hairstyle, another is styling), not grinding::process but a grind (a physical object that can be easily indicated in space-time, at the moment of its operation, not its production), not delivery::process but a delivery as a box in the hands of the client at the destination. For dancing, you cannot simply show its physical result (although the viewer may be "satisfied" or "interested", and the dancer may be "uninjured" - this could well be a result), but for a "work process" or something similar, the result can often be indicated, so describe this result in the material world - this is a more likely candidate for a system of interest.
The system of interest - is definitely not a process, but it surely behaves in some way during its functioning, it changes something externally, in some ways changes itself. If you have found some important verb for result descriptions, ask the questions: 1. who is behaving this way? and 2. for what result? Get two candidates for the system of interest immediately. It would be good to get the answers in "roles"/functional objects, and if it concerns agents, numerous roles may be performed by the same agent. But this is the first step towards considering the possibility of division of labor, which is important for the engineering of creation systems (if I am combing my hair, I am both a hairdresser and a client simultaneously. But the work can also be divided: assign the role of hairdresser to an agent who can comb hair better than me, the client. And the result? Hairstyle, the system of interest!). If an agreement about the result is made, then you can discuss different processes leading to it, different services of various systems that will help achieve this result (the system of interest).