It happens all the time (yes, I know I have a lot of decks, but I also have a highly organised storage system and database. I have to !)
This last few days I have been moving everything from deck 500 onwards.
| I have a problem just now !) To keep things right, I need them moving in order. There were maybe two dozen that were not where they should have been when I went to move the ones from that area. And ten minutes later, after I'd torn a fair bit more hair out, they would be back where I'd already looked, and giggling. Not to mention the four that hid together in a drawer I had emptied by feeling ALL THE WAY AROUND inside it with both hands before moving that batch up.Which meant that then had to go back six drawers and move four decks back up again to make space for the renegades.... I swear they did it on purpose.
What ALWAYS (so far) happens with mine is that they turn up where they should have been in the first place, and where I had already looked. I swear they do it deliberately. And I am not kidding.
We are talking tarot decks here. they have minds of their own. Even when they take up gang warfare !