You may turn a bad idea into a good idea — don't kill the bad idea prematurely. A bad idea can evolve into a good idea. - Martin Lewis Perl

Experimental science is a craft and an art, and part of the art is knowing when to end a fruitless experiment. There is a danger of becoming obsessed with a fruitless experiment even if it goes nowhere.

Imagination and obsession are the keys to getting a good idea. To help your imagination keep your eyes and ears open. Avoid the "not invented here prejudice".

I always look for colleagues who are smart, and who know a lot in many fields. The obvious advantage is that he or she may be able to solve the problem that has produced trouble in your work. Also smart and knowledgeable colleagues can save you time, and are interesting and inspiring!