For someone, such as yourself, who has been in software for 14 years I'm surprised that you'd write these words. Most people I've met with your years of experience realize there isn't a "wrong technology" there is a "right technology for the problem" and a "right way to use a specific technology". I suspect you're applying hindsight bias in thinking, "I could have gotten to where I am sooner if only I hadn't done the things I did and instead done these other things." For all you know you might have found a mentor who pushed you to be better at Java Swing and you could have been the person to "fix it" so to speak.