I draw a lot of crap but at least I am drawing. I also think I'm still getting better. I just have to put more effort into it when drawing.
I noticed if you don't put 100% in it from the start, and don't plan everything out correctly, then even erasing a lot won't really help you anymore. Then you are stuck with a shitty foundation and only can polish a turd. That's why it's so important to try to visualize what you want to draw in your head first.