Originally Posted by AslansMonkey
There's an episode of the Twighlight Zone from 1985 called "A Matter of Minutes." It's based on a short story called "Yesterday was Monday" by Theodore Sturgeon.
Anyway, in the TW episode a couple wakes up and discovers a construction crew "building" the next minute of the day. Every minute must be constructed by the crew before "reality" catches up and occupies the "set" for the next minute. In that episode they explain that sometimes they make mistakes and forget to put something in that is supposed to be there. This is why you sometimes look in a drawer for your watch and can't find it only to eventually find in in the same drawer a few minutes later. The workmen simply forgot to put the watch in there for the first minute you looked.
I would imagine nuts and screws get misplaced all the time by these work crews. Thats enough explanation for me.
In the movie industry it's called 'continuity'. They have a person on the set that watches for things like how much liquid is in a glass, or how long a cigarette is from scene to scene to make sure when they put the scenes together on film they match.
Maybe that's what happens. The 'continuity' person screws up and your tools/parts/fasteners get moved when they start to film the scene from a different angle.
I knew there had to be a better explanation that little green men who live in my garage.