The only thing that really matters about your name is how you feel about it. If you cringe every time you hear it, or it somehow makes you unhappy, its probably time to change it. Hopefully you're a citizen of a country that readily permits such a thing.

The only time it'd be good to change your name for professional reasons is if you're coincidentally an investment banker called Bernard Madoff, but even then that could possibly be worked in your favor.