You bet there are. Even in my place there are, and my wife and I both have pretty distinctive, pretty consistent taste.
There's a painting, for instance, that I hate. My wife likes it. So it's up. If you're married, you understand this kind of compromise.
It's not distinct enough from the other art we have to draw attention to itself. But it doesn't quite fit. So what does it say about us that it's on the wall?
If we were characters in a film, it would say that we don't have a really clear sense of what we like.
We're not characters in a film, which is why it's not a big deal. But in a film, it would be death. It's not consistent enough with the other art to define our taste, but not inconsistent enough to raise a question.
Communication depends on clarity.
If your character is neat, a little mess is not okay. If your character loves music, there's no reason for him to have a collection of shot glasses. Unless there's a reason for him to have a collection of shot glasses, in which case he needs to have them.
Let me hasten to explain that I'm not saying every environment in a film needs to be neat and orderly with only meaningful objects in it. What I'm saying is that you, Aspiring Director, don't have the luxury of developing subtle nuances of character in the same way that, say, a novelist does. A novelist can tell you about the shot glasses, then explain why they're there. Why they're perhaps ironic. Or a holdover from a time when the character felt a need to collect something. Or maybe a meaningful reminder to help a recovering alcoholic from falling off the wagon.
A novelist can even go on for pages about shot glasses that aren't there, that were there once, maybe, but had been tossed into a dumpster in a fit of rage by an ex-lover years ago and missed ever since. Shot glasses that might have precipitated the very breakup of the character and his lover from which he is only now, years later, beginning to recover.
There are only two ways to communicate character in film: what people see and what people hear. And as Steven Spielberg can attest, you can never be too heavy-handed with what people see.
Keep it simple.
Is that clear? I know, I know. Clearer than my own living room.