One time worked in an office building with a pretty shitty floor on the second floor. Wouldn’t have surprised me if it wasn’t really all that structurally sound, because I could bounce my leg, just like I am doing right now, and the dude sitting next desk over could feel it in the floor. I ended up moving to another desk to avoid the conflict with the coworker… and in case the building was shitty enough that it was a weak spot in the floor.