Why do I underestimate my own research ideas? Before continuing on working on a specific problem, I do plan on few things which have not been explored in the available literature. However, instead of developing them (in terms of mathematical models), I feel that my ideas are quite simple and not so novel. Sometimes, it also happens to me while I read research papers.

I feel this is one of my weakness which makes me unfocused on a particular problem and makes me switch to various such ideas which are flushed by me. 

Is it normal in research? How should I deal with this problem?
I hear you. I also know the flip-side of this phenomenon: Reading a paper and thinking: "That's a very simple idea they've published in this decent journal here. I could have come up with this on my way to work while riding the bike, would have written it down in a few weeks". But, alas, I didn't; someone else did.

I suggest the following procedure, although I can't claim that I've tested it:


Write down all silly ideas, especially the simple ones, and store them in a file; shortcut to your desktop.
Go through the list on a regular basis, every fortnight or so. 


Move the (still) infeasible ones and the (yet) too silly-sounding into a "discarded idea" file.
Pick a quite simple one that you find intriguing and highlight for later use.

Reserve an hour in the morning to write down why the simple idea is so simple. This should force you to think clearly about all the implications that you took for granted when you said "oh, that's trivial". Now, is this still a simple idea? Are there any follow-up puzzles and questions that perhaps aren't so simple? I bet one hour is not enough to write down all the stuff that's implied and needs to be explained in order for the problem to appear simple. There, you're drafting your next paper.