I've heard bitcoin compared to gold, as they're both finite; but if you drop gold, you just pick it back up.
Bitcoin accounts are better compared with helium balloons, helium's also finite, and mined, but if you don't handle it well, you can lose it forever. We all lose it forever.
Some might see this as a shortcoming, but I love it. If you handle bitcoin well, you can be certain it will become rarer (and more valuable) every time somebody else relaxes their grip on the string.