We know so much about the human machine, how it works, what the parts do and how they interrelate. But we still don't understand what really makes it go.
It's like being given a car but no fuel. We have the tools to take it apart and reassemble it. We have done this over and over and we have come to understand how every part functions. But without the key, the fuel, we cannot really understand what makes it all go.
So it is with creativity. We, as makers, are all creative in one way or another. We have to be. Even if we are not given to brilliant designs or what is commonly accepted as artistic ability, we still have to solve many problems in our daily routines. The more creative we are, the more likely it is that we will envision (imagine) the solutions. But, unlike the car or the human body, we don't really need to understand what makes it go in order to make use of it. We just need to allow ourselves to imagine.
Sometimes we create more problems for ourselves that we solve. But for me, that is the real fun of creative work. It's really little more than an endless chain of problem solving. An idea has to be fleshed out and manifested on the physical level. That's the time to move on and imagine something new.