Banks do that.

VC money is for the high-risk. A lot of their punts fail (companies die), so you need to make enough money off the ones that succeed that you cover all your losses and still make a great pile of money on top for future investments and profits.

The only way to make that stash of cash off the winners is to exit for high returns, and in the case of backing a winner to increase the stake over time so that your high returns are multiplied by the stake size.

This shouldn't be news to anyone. Did you think VCs were your friends?