A Warranty isn't a "get my money's worth" proposition. It's an insurance plan. Like any insurance plan, you're betting something, or multiple things will break and you'll save more money overall than paying out of pocket. The Warranty Company is betting that won't happen. They make a profit by playing the odds, and the odds are in their favor or they'd go broke. As many have listed already, there are a few things that could go bad, but many happen to be covered under a recall or otherwise not going to be expensive enough to bother with an extended warranty.
My speeding isn't the problem. It's the Slow Folks ahead of me that cause accidents!