Women may change (I haven't noticed myself changing... but I guess it's possible)... but men don't. This isn't necessarily a bad thing, but it can be if you're hoping for a 'fixer-upper' in a man.
If you don't like the way he is now, then you never will. Even if he was willing to try to change himself for you... eventually the his 'true self' will start to show again. Then the cycle will start over again... the cycle of him lying to you and to himself in order to be something you want.
It's usually better to be with a man you like from the beginning (flaws included). This works out better because he'll hardly change as time goes by. No need to lie to you or himself in order to be what you want... no accumulation of guilt and resentment as time goes by. Essentially you would have a much healthier foundation to base a relationship on.
"The weakest soul, knowing its own weakness, and believing this truth that strength can only be developed by effort and practice, will, thus believing, at once begin to exert itself, and, adding effort to effort, patience to patience, and strength to strength, will never cease to develop, and will at last grow divinely strong."
- James Allen