Sometimes they do. It depends upon what you are trying to portray. Some things are harder to convey than others. If I really get a character the group usually understands what I'm portraying. Sometimes I create a character that I can't connect with. Those are the ones that I have problems getting the personality across to the group.
I think "Sometimes" is going to be the defining answer here. As Kyr mentions, some concepts are harder to portray than others, even if they connect with the character well.
The medium makes a difference as well, since coming here, I've been forced to realize I rely on body language a lot. On the other hand, I don't have to worry about my voice sounding entirely out of place.
Edited: daishain on 4th Jan, 2017 - 12:12am
Honestly I am not fully sure, as much like myself I am not very good at figuring out what others think of what I do, say, or in the case of roleplaying give personality to my characters. Normally, in such cases I would need to ask the other players.
Most likely, I could see myself needing to explain what I am going for and seeing if that matches up with their own perception of my character based on how I am roleplaying them.
It's not necessarily a bad thing if the other players don't see your character as you intend. That is pretty true to life. A lot of people are seen by others differently than they feel they are. Think of the most annoying people that you know. I guarantee that they don't think they are and probably don't intend to be like that. They wouldn't understand why people would think that. Just a thought.
Fair enough, though such is something I worry about in real life. So I could see the same applying to my characters to an extend, as the thought of my character not being seen correctly is at least a little bit of a concern.
I don't see myself as a good judge of my own character when it comes to how others see me, so perhaps same could be said involving my characters. It may not be a bad thing, but it can be something that I think on at times.