I noticed in a recent convention I bought some cheap bin Image books, and I only discovered checking up later that I had the book already in my collection. That there was a different variant cover used.
Basically with variants, after the book is old, when you search bins, you can get confused and buy the same copies of books you already had! That really sucks when you think about it. And the cause of the confusion is simple, a variant cover is used. But what makes it worse is that it’s now common for books to have four or five covers an issue.