Just the luck of the draw. Any talent that is in your pet's pool may manifest. Just luck (good or bad) that one will manifest. If you do not like selfish talents, your only option is to hatch them out of the talent pool. Some selfish talents can be useful when you are trying to develop a single purpose pet. Ex: You want a max damage pet. So you try for 3 damage talents and two selfish talents that boost attributes that help with damage (power, agility or strength.)
