The problem I've seen is it makes sense to the person who set it up but when they leave it's not as easy or obvious for the person who comes in later to maintai

The problem I've seen is it makes sense to the person who set it up but when they leave it's not as easy or obvious for the person who comes in later to maintain it. If you have left behind detailed docs that may mitigate the issue. Also in some cases there is good reason to do it yourself but in other cases some people have a strong NIH syndrome and the value in the end to the company is not necessarily higher with a custom setup. In the end if it ends up costing more to maintain the system it's a net loss.