At the end of The Sixth Sense, Malcolm finds his wife having fallen asleep watching old video tapes of each other. Then she drops a wedding ring, the camera zooms in on her hand to show that she's wearing a wedding ring and finally it's shown that Malcolm isn't wearing one. This makes Malcolm realize that he is a ghost and has been dead for a year.
This seems like a strange way to make this reveal. I don't recall it being firmly established that Malcolm is a man who never takes off his wedding band. Both for him (especially with ghosts "only seeing what they want to see") and for the audience there are plausible explanations for why he might not be wearing his wedding ring at that time. (Forgot to put it on after showering, angry because his wife flirted with someone earlier, etc.)
Conversely, had the shot of Malcolm's hand shown that he was still wearing his ring, there would be three wedding rings in one place. Both Malcolm and the audience could have immediately recognized this as impossible, and a strong clue that Malcolm's ring, like his clothes and body, are just a ghostly memory.
Is there any reason, preferably based on interviews of the crew and cast, why the movie chose to show Malcolm wearing no ring?