After about a month, I had my first atty die on me. It was working fine, then I got on a plane and, when I got off, I went to vape and was getting no signs of life from it whatsoever. It just died in between
vaping sessions with no warning signs.
Right now, I have 4 in stock - two that are in use (I only vape a couple of flavors so one is for menthol and one is for cherry and cola flavors) and two new ones sitting with my stash. I usually take a spare with me when I go out, just in case, and, when the next one dies, I'll just pick up a new one with my next juice order so I always have a couple of new ones handy for when an exisiting one goes kaput.
I found that was a good part of my initial, upfront cost when I started
vaping and found that I liked it - I wanted to make sure I had enough spare parts so if an atty or battery died, I wouldn't be left high and dry.