https://youtu.be/2oBGNIC4zeo

I have a demonstration footage and a possible explanation.

But to summarize, if a bot armed with a shotgun encounters a weapon spawn, they may get confused and keep swapping between their favorite weapon and shotgun. This will also happen if a bot with a tier 1 shotgun finds tier 2 weapon spawns (non-shotgun), and gets stuck in the same loop.