Inspiration is uncomfortable. Not the actual outcome. The process itself, leading up to the inspiration and the moment of clarity, tend to be slightly irritating.
The main issue is timing. In many cases, good ideas come at inconvenient moments, right before falling asleep or while waking up in the middle of the night.
Sleep definitely plays a significant role. Salvador Dali, for instance, knew this. The artist allegedly sat down in a chair while holding a spoon. Right underneath, a metal plate was positioned so that when he would enter a so-called hypnogogic state. When dozing off, the spoon would slip out of his hand. The clattering sound would then wake him up, presumably leaving him very inspired.
If inspiration is indeed plentiful while being inconvenienced, it would be possible to reverse-engineer. The question is, how much are you willing to sacrifice for inspiration?