[necovek]

A startup of 5 people likely exists in a "system of patronage". And I don't think that in a negative sense: 2 people will sometimes be equal in their abilities or have their distinct domains they are experts at, but as soon as their opinions clash significantly, they either continue with one being dominant, or separate. Just look at the number of fallouts between best-friend founders.

It's extremely rare that both will exude similar approach to collaboration and compromise equally (and perceive it as equally) to keep a stable business relationship.

That's just human, and what enables things to move forward (other option is death by commitee).