In any musical situation, whether it's a gig, a rehearsal, or a jam session, there's one person who holds it all together. Even though everyone contributes, there's one person who takes the responsibility to make sure it works.
They're the person who finds a replacement when the drummer's car beaks down and they can't get to the performance in time. They're the person who brings extra copies of the music in case someone forgets theirs. They're the person who who spends the whole morning finding an improvising cellist to play that cool jazz/classical hybrid piece the guitarist composed.
As I said, even though everyone does have an important role, there's one person who makes sure "it gets done." One person who makes sure it happens, no matter what.
Be that person.
Want to enliven your practice sessions? Here are 30 Ways to Practice a Piano Piece. Have fun!