It's very hard to learn form gambling mistakes. First of all you have to realize you are making a mistake and not just luck. Most of gamblers blame the luck and that is all for them!
To bad for those who can't accept their mistakes because they can't move forward and just have self pity all the time and just even end up broke. We're all humans and making mistakes is just usual so learn from it but what's unusual is when you always commit the same mistakes all over again. It's different story tho.