First of all sorry you got downvoted, because this is actually a pretty good response.
You are indeed correct that not all ideas (or theories) are easy. I think in the case of flight the practicality dominates the theories because they have to be combined just right to actually work.
Whereas your example of relativity, it's indeed the theory that is the hardest part (and Einstein got the proper recognition for that, not the one who practically applied it).
Going to make a weird comparison here, but it's basically like a chicken coming out of an egg. We only see an egg at one moment, and the next there is a chicken coming out. We don't really notice there has been a lot of stuff going on within the egg a long time before it came out. Seems the same as with innovations or discoveries. Suddenly it seems to be there.
But I stand corrected that it's not always the practical application that dominates, sometimes it's indeed the theory that is the biggest achievement.
You are indeed correct that not all ideas (or theories) are easy. I think in the case of flight the practicality dominates the theories because they have to be combined just right to actually work.
Whereas your example of relativity, it's indeed the theory that is the hardest part (and Einstein got the proper recognition for that, not the one who practically applied it).
Going to make a weird comparison here, but it's basically like a chicken coming out of an egg. We only see an egg at one moment, and the next there is a chicken coming out. We don't really notice there has been a lot of stuff going on within the egg a long time before it came out. Seems the same as with innovations or discoveries. Suddenly it seems to be there.
But I stand corrected that it's not always the practical application that dominates, sometimes it's indeed the theory that is the biggest achievement.