Collecting sets you can't complete

[Exhibitman]

If you collect certain things, like boxing as Greg noted, or many nonsports sets, foreign sets, etc., defining a set can be a challenge and for all intents and purposes, finishing a set can be impossible. You just accept that it will never be completed and you do the best you can.

One of my favorites is the H815 and related Adam Hats premiums (whether they should all be H815 or H-Unc. and H815 is an academic debate among cataloguers). They were made for store displays in Adam Hats stores and are legitimately a rare issue. No way to know how many there are or who is in them. I'm a handful away from the complete known sports checklist, but they are nearly all baseball (I need Grove, Hubbell, McGraw and boxers Maxie Rosenbloom and Dave Castilloux) so no realistic chance of finding them except by luck. Uncatalogued ones pop up from time to time. Here's the Jack Dempsey and the Raging Bull, Jake LaMotta: