Following on from yesterday's post about 90% complete, I'd estimate that the tangible gains from completing projects come around:
90% -- almost none of the gains (maybe some experience)
99% -- maybe half of the gains
100% -- all of the gains
Thus, going from "0% complete" to "90% complete" would get you only a few random lessons, and not much tangibly. Going from 90% to 99% would give you near-infinitely more than that, and going from 99% to 100% would double your returns.
In that light, doesn't it make sense to maximally complete the opportunities you have onhand, rather than seeking new ones so often?