When I was a teenager, I used to dress and "release" myself. But I didn't dressed just for the pleasure (at least at the beginning). I got dressed because I had an urge to feel more feminine, and when I got dressed, the arousal was a consequence, not the objective of getting dressed.
It was amazing for me how feminine I would feel and look (specially when I was much younger). Back then, I was extremely shy and with very low self esteem. I thought that no girl would ever love me, and this feminine version of myself was the closest I'd ever get to a girl. But all these thoughts came little by little.
But at the beginning, masturbation was a consequence, not the objective of dressing. And the arousal of dressing was simply higher than any other thing I have experienced at the time.
I also have to say that I'm happy this has changed. Self gratification can't be compared with really making love with somebody you love. My humble opinion is that self gratification is selfish, and I don't understand how can somebody say that masturbation is a substitute or a complement to normal couple relationships, because it's more convenient, or less trouble than synchronizing agendas with your SO. At least it's not the case for me.