Lexmark laser prints ca. 1991
Back in the early 90's, we purchased a number of Lexmark laser printers. They were pretty good, but one had continual issues with grabbing a massive wadge of paper from the tray and regularly munting the feed roller. We could not understand why this kept occurring, until we sat with the secretary who had done this several times and watched her reload the tray. As she reinserted the tray into the printer, we saw that she flicked it slightly sideways - checking the tray mechanism revealed that the paper was only held in place on one side, and a small lateral force was sufficient to dislodge a pile of paper, ready for the next pickup.
Suffice to say, we didn't stick with Lexmark as our printer supplier.