I guess we are talking here about a personal experience.
So...
1. A joke from KSA. Removed from an album but still ExMt
2. A joke from Beckett This card was graded as Good but when I sent a much nicer card to them with just a little glue stain on 1 corner of its back, it was returned as ungradeable (fortunatelly it was 1954 Parkhurst G.Howe and I easily got $175 for that card later)
3. PSA reality. Beautiful ExMt front, back is covered (hard to see) with a glue. I guess I should have asked Gerry how to remove it.