To expand on this (for Non-YC situations): 1) VCs want to keep the door open for later by not outright saying "No.", since there's no incentive for them to do

To expand on this (for Non-YC situations): 1) VCs want to keep the door open for later by not outright saying "No.", since there's no incentive for them to do otherwise. 2) VCs follow the herd (need social proof), so they will often wait for that area to blow up, or wait for another VC will be the "lead." 3) VCs today would rather be late investors after the concept is proven and they can move hundreds of millions of dollars around to get even more hundreds of millions. Also note that VCs like to imply that they have integrity, but that's often not true: 1) They've had meetings to collude against YC (documented in the press.) 2) Silver Lake Partners revokes employee shares if you leave before 4 years ("In it to win it.") (documented in the press.) 3) Shocking personal anecdotes.