I imagine it like this: First we do the useful stuff as much as we can. But at some point it slows down and halts. Then with that knowledge doing useless stuff is easier. So we widen the search. Maybe most of them are really useless but few that can make a breakthrough is enough. Now back to useful stuff. This process is not discrete of course it’s more dynamic and fluid. Does this make sense?
I imagine it like this: First we do the useful stuff as much as we can. But at some point it slows down and halts. Then with that knowledge doing useless stuff is easier. So we widen the search. Maybe most of them are really useless but few that can make a breakthrough is enough. Now back to useful stuff. This process is not discrete of course it’s more dynamic and fluid. Does this make sense?