There's been multiple situations where I can't pick up a weapon or piece of gear for whatever reason. Usually bugged. But something like a lost loot cache (borderlands 3 has the best, and only example i know of) would be exceptional. A place in your apartment where the loot you cannot pick up or you simply don't notice gathers during your gameplay. Then before you log off, go there and claim all the loot instead of missing out on it.