For every good idea, expect to have five, ten, twenty wrong or useless ideas. You cannot avoid the bad ideas if you keep your imagination free. There… - Martin Lewis Perl

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".

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.

Common elements of creativity are originality and imagination. Creativity is intertwined with the freedom to design, to invent and to dream. In engineering and science a creative idea is useful only if it meets three conditions: the constraint of the natural laws, the constraint of cost, and the constraint of technical feasibility.