You start with a research problem and 1 possible solution. Work on the solution for a few months, and a second possible solution presents itself. With no way of judging which is better, you continue working on the first one....
After a few more months of work, the epiphany hits you that this won't work. Most probably.
But switching to the second solution is tough.
It has no guarentees either.
It could be better. It could be worse.
Finishing work on the first solution will take a few months, the second many more months....
Comparing the two - a lifetime.
Existance of an optimal solution not guarenteed.
And the first solution might just be workable on a short term basis.
But the second now seems more exciting - the first is now boring...
What do you do?
Epiphanies are tough.
Life problems - tougher.