Is being "self-serving" the same as being "self-centered"? While looking for an answer to this question, I saw this previous question on the difference between "selfish" and "self-centered". I generally agree with the top three answers in that question (i.e. the answers provided by @FeralOink @Bill and @mozen), but want to know if and how "self-serving" differs from "self-centered."
Are the connotations or actual meanings different, or are the words essentially interchangeable? I think "self-serving" implies something about purpose, while "self-centered" implies something about focus, but I am not sure, and I have not been able to flesh out the difference in a satisfying way.