90% of all companies funded by this VC will fail. Of the remaining 10%, some will be middling successes. One or two companies will be really great. But the VC has a problem: his LPs expect a return over 10 years (or whatever the lifetime is) that is as good as the market (simplifying, but this is basically true). If the one or two companies that succeed only become worth a few hundred million, he's actually delivered a sub-par return for his LPs. So the one or two companies that succeed must _really_ succeed, or else the VC is going to have trouble with their next fund. Someone did the math and showed that a 10x return on those successful investments is the minimum for the fund as a whole to provide a good return for its LPs.
All this means that when a VC looks for deals, he can't waste time on lifestyle businesses and the like. Billion dollar companies or bust. Keep in mind that this is not true for people who write smaller checks (like angels).