Failures have not been a problem, even with hundreds of intel 2.5" SSDs in production, a single one hasn’t failed yet. One or more spare parts are kept for each model, but multiple drive failure hasn't been a concern.
All of those 2.5" Intels though, still trucking along! We're looking at some P3700s PCIe NVMe drives now, blog post coming about that.
For comparison, for a while we nearly had a 1 to 1 dev to killed (consumer) SSD in work machines (see: http://blog.codinghorror.com/the-hot-crazy-solid-state-drive...). Granted, we did adopt them (see: http://blog.codinghorror.com/the-state-of-solid-state-hard-d...) for local dev use much earlier than we started putting them in servers.
I've killed 2 in my time here, though I do horrible big-ish data things that are either not SSD friendly or actively hostile.
That said, all the SSDs I've had have taken repeated pounding with no complaints. I accidentally swapped a few terabytes to swap on an SSD, and was simply surprised that the job I was doing finished faster.