What drove me nuts was when they were inconsistent about Monica's OCD or didn't address it in a way that made sense. Take the fire in Rachel's and Phoebe's apartment. Monica brings Rachel breakfast in bed but then won't let Phoebe eat cookies unless it's over the sink? Rachel was shown to be a fairly neat person but so was Phoebe so why was Monica fine with Rachel eating in bed but not Phoebe? Yes, cookies leave crumbs but Rachel could have spilled something on the bedding. We saw her spill spaghetti at Joey's in the same episode so we know that it could have happened at Monica's. And Chandler was also shown to be worrying about "crummies" so I have no idea what we were supposed to think. Maybe Rachel was really good about cleaning up her spills and hiding them from Monica? Lulling Monica into a belief that Rachel could be trusted with breakfast in bed while making everyone else eat the cookies over the sink? But then Rachel knew about eating cookies over the sink AND we saw Phoebe and Ross eating the experiment cookies at the table in a different episode so I don't know.
I would have liked to see someone address Monica's obsessiveness about cleaning, being in control, and her competitiveness with regard to kids. I don't have much memory of the last season so maybe there is a scene I've forgotten but, if I knew her in real life, I'd ask how she can be confident in her abilities to parent a child when she HAS to win all the time, or if she had any plans to address her obsession with cleaning, or her need to always be in control. Because kids are messy, they break things, they make mistakes, and they can be stubborn. If I knew someone as anal as Monica in real life I'd advise her to talk to someone and make sure she had the tools so that she wouldn't get excessively upset when her kids are being kids. Monica could easily become one of those moms who gets into fights at the soccer games because the outcome matters more than if the kids are having fun. Her obsessive cleaning could put unnecessary stress on the kids and then they start freaking out about something like spilling apple juice. And Chandler's tendency to let Monica be in charge would only add to the stress because he'd be freaking out too. Phoebe moved out because "I need to live in a place where people can spill!" and that was in season 3 when Monica was presented far more reasonably about wanting things clean. The woman she became by series end is not one I would entrust with a child unless she had lots of therapy (this is true for all of them of course but I'm focusing on Monica).
