In my experience, it's incredibly common. I don't think I've ever worked at a place where this didn't happen. It's not mystery as to why, either. Upgrading too

In my experience, it's incredibly common. I don't think I've ever worked at a place where this didn't happen. It's not mystery as to why, either. Upgrading tools is expensive by just about every metric, not just financially but also in terms of disruption. Also, using the latest version of anything carries a real risk: the latest version is generally the one that is most likely to contain serious problems. It's better to sit at N-1 as a general rule. Deciding not to upgrade, in the absence of a benefit that can offset the cost, is not entirely irrational.