There are some conditions we have to create if you want to have a group of people as a team:
- Person competence, you need people with enough competences, some of them complementary.
- Clear & defined functions, for all team guys and clear channels of communication (inbound/outbound).
- Authority, to decide on some aspects, features, behaviours… that provide a piece of freedom that enable them to act in their style.
- Resources, to be able to perform their functions.
- Protection, we have to protect our teams: their authority, their decisions, their delivery conditions cannot be interrupted,
- Control, there should be a way to check that performance of the team is right and that they are working through their goals.
There are more conditions, these are just some of the basic ones.
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From the "soft side" that could be: guidance — a goal, common theme and/or set of values, and friendship.
Passion / hope / "can do" attitude would be the marshmallow to the list. A very important marshmallow too.
Thanks for a nice summary.