I imagine the problem is how do you pool the risk without being able to assess with confidence who will succeed and who will fail? And how do you prevent freelo

I imagine the problem is how do you pool the risk without being able to assess with confidence who will succeed and who will fail? And how do you prevent freeloaders who don't expect to succeed wanting a share? And if you could make that determination accurately, why wouldn't you use it to avoid pooling risk among all but an extremely small pool?