Mark Suster says it best: Star­tups break­down be­cause of founder in-fight­ing. What we’ve been say­ing for years! Here are some key points of his:

But there is no such thing as “no pol­i­tics” since we’re hu­man be­ings and we’re ge­net­i­cal­ly wired for pol­i­tics. It’s called so­cial in­ter­ac­tion and un­der­stand­ing peo­ples’ mo­tives, what makes them tick, who they don’t get along with, what ri­val­ries ex­ist, etc. is a very im­por­tant part of be­ing a leader.

It’s why I wrote a post out­lin­ing why the job of a CEO is of­ten “chief psy­chol­o­gist” – es­pe­cial­ly if the com­pa­ny grows be­yond 20 em­ploy­ees.

He in­cludes lots of great ex­am­ples of part­ner­ships break­ing down, in­clud­ing some of the less-known ones (Foursquare).

Worth the read in its en­tire­ty.