After about 20 standard Ubuntu installs it was toast. BUT, that used much older tech than the SSD's of today.
Failed after 20 Ubuntu installs? That has to be a serious outlier. At that rate you'd have a production drive failing in probably a few weeks. I know someone who uses SSDs as the cache drives for their SAN and they haven't had any failures in a year or so.
I think that there's a lot of paranoia about burning out SSDs. You shouldn't go out of your way, unless you're testing like you were, to bury any drive with write activity but I think that being afraid to write to the drive is overkill. With a 5 year warranty and adequate backups I wouldn't worry about it in the slightest if I had the cash and the need for 500 MB / sec throughput.
Don't defrag them, it's pointless. But don't worry about wearing them out with a normal workload. That's MHO.