I pretend not to understand things just to avoid extra work

At work if someone asks me to do something that technically isn’t my job, I’ll sometimes act just confused enough that they give up and ask someone else. Not in a way that makes me look bad, just enough to make them think "Eh, never mind."

I could probably do it but I also don’t want to accidentally become the go-to person for something I don’t even want to be responsible for.