Board Thread:WARNING ALL USERS False Info\Spoilers/@comment-69.121.172.69-20130820040029/@comment-11533671-20130824151039

90.244.144.26 wrote:

Since we all know this is really due to budgetry reasons it may well be a plot hole which will never be filled. If it is ever filled it will be something to do with the hale family. They are the only werewolfs who we have seen take any form which was mor wolf than human. It was stated by Gerard that Talias ability to shapeshift was rare, probably meaning only Hales can do it. Peter's form was perverted because he perverted the natural line of succesion within his own family by murdering his niece. Derek probably didn't shift through fear of not being able to control it or because he further perverted the natural line of succesion in the worst possible way by killing his uncle, leaving the ability dormant until an alpha ascends in that line without stealing it from another According to a tumblr interview at the beginning of S3: Don't expect to see Derek's transformation into a full alpha wolf this season. "When [we] can afford that level of CGI maybe. How about when we do the 'Teen Wolf' movie?" (Jeff Davis)

Perversion has nothing to do with the shift. Talia's rare shifting isn't a trait that ONLY the Hale family has, it just happens to be her and Laura that have been seen to have this ability so far.