I'm proud to say I retired more k8s clusters than I created. And I've created 5 production ones, still in production.

One that I retired was used for serving ftp(among other transfer stuff), ftp of all things, it needs to have ports open and routed back from the client. And for extra points they had the pods capped at 1 cpu. And I had to explain the thing to the perpetrator and their boss, madness.