One often hears established mathematicians commenting on the work of younger ones as "pointless generalizations". Sometimes, these pointless generalizations are used by somebody else to prove a result that attracts attention, and then the same established mathematicians will say "OK, this proved to be useful, but it was just an easy exercise that could have been included in the proof of the big result". It might take some more time before the younger generation actually recognizes the value of these pointless generalizations: not everything can be world shaking or even first class.