That's a truism in our industry that far too few people understand, much less take advantage of. If you're good, you don't need to worry about your career all that much. You can go off and travel, join flaky startups, and otherwise sabotage your "career", and know that if it all falls apart you'll land on your feet. So long as you're demonstrably good at what you do, you can always pick up a good contract on short notice.
There's a flip side to it, of course. If you find it hard to get work in this industry, you might want to consider the possibility that maybe you're not quite as good as you think you are.