A real revelation
What happens is, once you have a problem you want to solve, you have some idea of how to approach it. You try to work it out, and if you can solve it the way you thought you could, it is done, and it is not interesting. You have done it, but it does not give you a thrill at all. On the other hand, if it is a problem in which everything falls into place, except for one thing you cannot do; if only you could do that one thing, then you would have the whole thing, but this foundation is missing. So you struggle and struggle with it, sometimes for months, sometimes for years, and sometimes for a lifetime! And eventually, suddenly one day you see how to fix that small piece. And then the whole structure is complete. That was the missing piece. Then that is a real revelation, and you enjoy a satisfaction which you cannot describe…It lasts until you write it up and submit it for publication. Then you go on to the next problem!