Amajor obstacle to developing good human relations skills is that

A major obstacle deterring a person from developing good human relations skills is that few people have common interests with the persons around them. everyone has diverse interests and preoccupations, and this halts them from engaging in contact with other people thus being unable to find a person with similar interests and making it harder to relate to strangers or a person who is all but familiar to oneself. 
-hope this helps