Now usually when people start power moves they want to get the move because it looks cool and it'd probably feel cool too. However the effort required is unfair sometimes, not only because your body isn't naturally inclined to do this but you have a serious chance of getting injured. The fear and adrenaline rushing through you when you go around once is quite an experience but before you even get to the big moves you have to start with the basics. For example you think you can just start learning windmill because you watched it on a video once? Nope your wrist isn't ready, nor is your capability to handle the fear. I remember I first tried doing it without any knowledge, all I ended up with was a bruised body. And I do mean that literally because my entire body was black since I probably hit every part of it. "How the hell can this move be so god damn hard to learn?" Was one of the first thing I spoke when I started it. It took me a solid 3 months just to go around several times and even than my speed wasn't up to par and it wasn't clean.
Power moves are ranked according to several categories, and the more you do them the better you'll get at it. I'd say the categories go as follows:
Execution - Basically how you get into the move and start it
Cleanness - Whether your legs are sloppy or flexed
Speed - Self-explanatory
Difficulty - How hard what you're doing is
Flow - How you connect your power moves
Creativity - What you added to the power move to make it yours
The more you have of those categories the better you will be(I might of missed a few but I think I got most of them).
I used to hate power moves since I started with style. I learned freezes, footwork and toprock first before I even touched power moves. To me they are probably one of the most hardest things in this dance because I'm just not crazy athletic and I'm pretty heavy to boot. Progress is really slow and sometimes you want to quit because of it, god it's depressing sometimes. When you think you're getting the move the next day it feels like you're going backwards! That's complete BS. There's all these subtle nuances that can make your power move learning experience that much faster but sometimes your body won't listen.
I really look up to those bboys that can perform and execute these moves with the finesse and expertise they do. I know just how hard it is and quite often I'll see improvement in many bboys power moves, going beyond what I thought was even possible. People will grab their leg while spinning, go up into an air flare, land onto their 1 hand into a jackhammer and than pop onto their head into a complicated position. You know they practiced hard and deserved props for that.
I honestly think that bboying shows how far you can push the human body sometimes. They do these moves at such a fast and incredible rate that it boggles the mind sometimes.