Ideas are like puppies. If you chase them, they'll just run you ragged until you're so frustrated that you wonder why you ever wanted them in the first place!
But most of the time, if you are relaxed and casual, the puppy--like an idea--will come to you and curl up in your lap, beg for treats, jump up for an ear scratch, or otherwise beg for attention.
Those are the kinds of ideas I want as a writer. Ideas that come naturally, often as a surprise, and demand my attention. Not some elusive thing that I have to chase down and force into submission.