Totally, and thats pretty much all that can be said. If you program more, you're likely going to be better than had you not (by how much is another question).

Using this as a way to compare different people, on the other hand, is foolish. Just spending time coding is going to do little to improve your skill assuming you're past the stage of just starting out. It's how much you're challenging yourself, and how you handle that challenge that makes a difference.