I think in part this is because the founders reach the point where they feel it's 'enough' way before VCs do, because VCs are risk hungry (distributing their ri

I think in part this is because the founders reach the point where they feel it's 'enough' way before VCs do, because VCs are risk hungry (distributing their risk across dozens of deals makes that easy) and want to roll the dice again and again. In the end, i believe that timeline of the VC's fund existence preclude them from meeting their return goals otherwise than through exits.