Comment by remus

I think you're right to an extent (it's probably fair to say e.g. Einstein and Euler advanced their fields in ways others at the time are unlikely to have done), but I think it's much easier to work out who these people are after the fact whereas if you're dishing out a monster package you're effectively betting that you've found someone who's going to have this massive impact before they've done it. Perhaps a gamble you're willing to take, but a pretty big gamble nonetheless.