My Powershot S100 had a similar problem. Beep beep, "Lens Error", shut down. I definitely didn't drop it because I was holding it when it happened. And I didn't get sand in it (as far as I know). It was just a year after I bought it so Canon wouldn't fix it. Even though they have a recall notice, my serial number wasn't within the range specified on their site. I've owned several Canon's before but no luck getting any support from them after warranty is up. They do reject you very politely to their credit. If you google "lens error s100" you actually see that this error happens quite a number of times. I think that's surprising, considering this camera was $420 purchased new.
Out of desperation and abandoned by Canon, I decided to fix the thing myself. I ordered a replacement lens assembly from eBay, and a lot of little screws later I had a working s100 again. It was amazing, I felt like some kind of genius and bragged to all my friends. Unfortunately that only lasted about 2 weeks. Then, even more surprisingly, beep beep, "Lens error".
tldr; I think it's probably a great camera just made with crap parts