I Hate Unexpected Visitors
I wouldn't say I "hated" it, but I just thought that it was sometimes annoying when I'd get a knock on my door from someone who didn't call/text/IM me to say they were stopping by. At least call me when you're leaving your dorm room or when you're walking towards my dorm building. There were times when I'm just chilling in my underwear in my room alone..lol..and it was just annoying to put clothes on to get the door.
Sometimes I just flat out ignored the door, depending who it was. One time though sophomore year, some guy who lived on my floor came by to ask for toilet paper..I wonder what he needed that for. Eww 
When I felt friendly though, I'd leave my door open or cracked and dormmates were free to just stop by. That was the exception :P
