There is so much old and creaky stuff lying around and people have no idea what it does. Beige boxes in a cabinet that when we had to decommission it the only way to understand what it does was doing the scream test: turn it off and see who screams!
Or even stuff that was deployed as IaC by an engineer but then they left and so was managed “clickOps”, but documentation never updated.
When people talk about the Tier1 systems they often forget the peripheral stuff required to make them work. Sure the super mega shiny ERP system is clustered, with FT and DR, backups off site etc. But it talks to the rest of the world through an internal smtp server running on a Linux box under the stairs connected to a single consumer grade switch (I’ve seen this. Dust bunnies were almost sentient lol).
Everyone wants the new shiny stuff but nobody wants to take care of the old stuff.
Or they say “oh we need a new VM quickly, we’ll install the old way and then migrate to a container in the cloud”. And guess what, it never happens.
Well I’m already a bad programmer, at least I save time /j