It's bad that there are half forgotten systems but almost every sizable business that has been around for many years will have this. On mobile, but there's a famous story of a server that had been drywalled over and had been running just fine, unnoticed and unattended, for years.

It's good to see that maintenance is rewarded at Google at least occasionally. I only ever hear that it is only new products that are rewarded. And I notice new people piling on to issues in their product trackers that I've been following for years.