i think you have to have a natural leaning towards it, both nature,genes whatever you want to call it and often the way you are raised (possibly becaue people tend to automatically react to a Dominant or submissive person automatically to some degree or another) both play a part in it in my eyes and the only thing in my opinion that has to be 'learned' whether you are Dom/me or sub is how to break free from the inhibitions and expectations society has given us which has been installed in us throughout our lives.

and some are more comfortable than others with that, if its too much of a struggle than id say its more of a want..a bit of fun than a need and a character trait and when thats the case its fun to play at it from time to time but thats as far as it will ever go without real inner conflict.

just my thoughts.