Keeping to one's self, avoiding interactions, and ignoring the world around us are common personality traits. Some feel that by living this way, confrontation will be avoided. Others may be persuaded to feel that interpersonal interaction is unnecessary and a waste of time.
Whether it be these or other reasons, isolationism is not in agreement with the example of our Savior. He commanded "Love thy neighbor," "[have a] love of God and of all men," and "as I have loved you, love one another." His life exemplified these commandments. As brothers and sisters we chose together to come to earth, and only by working together in unity can we make the world a better place.