[moffkalast]

I'm sure this is referring to the expected value in something like say, a dice throw. If the chances of winning when picking a certain number are 1/6 and the payoff is 6x the investment then the expected returns after a large mount of attempts are known and would be zero. I'm sure this is widely applicable in gambling.

[beardedetim]

Exactly the right term to use: Expected Value. If we have 1/6 chance of winning and each win gives us 6x, we have an EV of 0.

Poker is a great game to learn to understand EV/variance.

[mcguire]

I wonder what the expected value of entrepreneurship is?

I rather suspect it is significantly negative, because most new businesses fail and the venture capital system means gambling with someone else's money.