You can find the following article of interest.
http://www.qsm.com/process_01.html
But, to answer your question, it is difficult to understand the process that you are using. For example, a waterfall model will require a larger team than the flexible XP method.
I was in a team with 13 members, but this usually breaks down into smaller teams, each of which works on specific tasks. If a team is large enough that politics comes into play, it is too large. You can have a large number of people who can work well together, all of them are focused on completing the project and are not looking for their own interests, and a large number may not cause problems, but having these types of people is unlikely.
Everything that is more than 9 people is probably too large, because it is divided into smaller teams, so if the team is large enough to break into small teams, then just small teams will be the size of the team and understand that what you started, it was too big.
James black
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