How, how long time, how much cost
Especially bigger initiatives also need involvement of the wholeness team, in order to roughly understand how long it will take, and the steps and iterations that are needed to reduce the complexity to a manageable level.
The wholeness team will also consider the possible need of a platform, which can be used by different parts of the organization. To be efficient, platform thinking with modules is an important part in order to be efficient, and to continually keep the structure of the systems designed architecture with proper interfaces and APIs. That different parts of the organization develop about the same functionality without consideration of the wholeness, will rapidly become an architecture that cannot be handled anymore, leading to a dead product no one dares to touch.
The higher complexity, which is common especially when doing new products or new platforms, the more knowledge needs to be gained, which directly means a higher unpredictability in when the initiative can be ready. This will of course have an effect on the actual time needed for the initiative, but it will also have an effect on the lead time considerably if the complexity is high.
Cost is always an important parameter, which of course also will be calculated, especially from how long time an initiative will take, where the actual time and the lead time need to be distinguished.
If the initiative is prioritized, it is put in the prioritized backlog, where the wholeness team later in the process, may continue to develop the needed overall architecture, before the team of teams will continue with the architecture and functionality within the parts.
For more information about the actual management of going from unprioritized initiatives to prioritized ones, please see this article.