some problems, they can usually be corrected. Usually just a corrupted index or permissions. When an SSD goes, it's gone. That's been my experience. And even if you have a back-up, such as Time Machine, you are often screwed on older machines. This is because you can't reload the OS, because Apple doesn't think you are licensed for the upgraded version, but the hardware will no longer accept the original version. That's why I like SSD for my boot drive, but I clone a copy of it periodically with Super Duper.
As always, if anything is critical, you need an off-site rotating back-up, and real time fault tolerance.