I consider guitar successful when I have fun playing it. I've set goals in every aspect of my life from my job, to financial, to working out, to golf and candidly, it burned me out - always trying to achieve something and get someplace. I tried guitar 15 years ago and gave it up due to "lack of progress".

Took it up again just to enjoy wherever it took me on a given day. I think one of the things I like is there is no "scorecard" (and I love music BTW)...I know when I make a mistake but I can just leave it there and move on.

Learned a bad version of "Needle and the Damage Done" and "Melissa" - just enjoy the parts I recognize :)