For every innovation, there's will come a pack of naysayers without the talent, tenacity or luck to accomplish the same feat who will claim (usually long after

For every innovation, there's will come a pack of naysayers without the talent, tenacity or luck to accomplish the same feat who will claim (usually long after the fact) that 'anyone' (usually implying themself) could have come up with said innovation. It's a good sieve to weed out folks not worth wasting time on.