"burning out" only happens when you dont add fuel to the flame. If someone is passionate about what they are working on, they wont get burnt out. I can easily see getting burnt out on one technology or another, but the more code, the more I want to code and learn more.

If someone programs at the same company doing the same tasks for years until they hate programming, then I really feel no sympathy. Get a different job...its easy. Do side projects...even easier. Adding fuel is easy. Letting it die takes effort.