Teams let people do what they're best at. You can have research/science people and development/craftsmen people and marketing/business people. Each can concentrate on getting really good at their talent, at the same time that they can help out with the other people's tasks or substitute for someone else, while they take a needed break, or just give you useful feedback and a shoulder to whine on.

Symbiosis. Dunno. Feels a lot like frenship.