Watching this recently and there was an episode where Joey was offering to re-tile Monica's bathroom floor. Monica was saying that it didn't need to be done so Joey moved the laundry hamper from it's place in the bathroom in order to point out the difference in colour between the spot that had been covered by the hamper and the rest of the floor.
Monica is supposedly a total clean freak yet we are meant to believe she never moves the clothes hamper to clean underneath?
Similarly, when Chandler discovered the locked door in the apartment that no-one had ever mentioned / commented upon previously and it turns out it's full of junk piled inside the closet. Didn't fit in which the character of Monica at all.
I know I have too much time on my hands but both of these scenarios seemed like a bit of lazy writing to me.