Boki, First you have to decide if you're going to play the game, or tell the truth.
The game says there is a "process" that takes "inputs", generates "subtasks", and "schedules", which go to "motivated programmers" that "follow the clear directions", and use "leading-edge tools" to generate "Quality code" that can be "integrated" and "tested" and "shipped".
As you might have guessed, a lot of us that have been in this biz for a few decades use a lot of "quotes" around "concepts" that are mroe akin to Fairy Dust than to anything tangible and usable.
In the real world, you have a customer, who almost always, cannot be troubled to write down what they want, or has already written a 400 page spec, having nothing to do with reality or practicality.
Then you have managers, who are usually failed programmers, who make wild-ass guesses as to who can do what in what time.
Then you have programmers, who sometimes are skilled, but often have faked their knowledge, taken credit for what others have done, or are sincere, but extremely slow or buggy or idisyncratic programmers. or they're drug-addled, or have family problems, or gotr burnt-out and/or screwed by the last project, or have a grudge against management.
Then you have "tools", which range from the totally unusable way up to the barely adequate.
So decide, if you play the game, you'll have to lie, lie, lie, lie, to yourself and others.
Or you could try to be truthful and say "hell, nobody can plan your typical software disaster". Point to famous failed software systems: DBase III, TSS/360, The IBM FAA mess (12 yrs, $8 Billion, IIRC). SAGE (many billions, 15 yrs?), the FBI mess (years and several 100 million $), etc... etc.... etc.....