Warren Buffett has described PE as a horrible investment class populated entirely by grifters who lock up your money for 10 years and fuck around with it, producing awful returns. The way he describes it, VC sounds very similar from a LP's perspective.
So why does anyone invest? Buffett's theory is that LPs are mutual fund and pension fund managers who like the fact that there's a 10 year lockup in a private, illiquid investment because it means that the value can't be marked to market. They won't still be managing the fund at the end of the lockup and in the mean time they can mark to expectation and let the next guy deal with the fallout.