Sue's hairstyle, as well as the texture and length of her hair, and the color, changes from scene to scene, and even at times from shot to shot. This was due to movie re-shoots.
This reboot was given the green light due to the somewhat disappointing box-office numbers of the previous two "Fantastic Four" films. A reboot was considered "less risky" financially. Sadly and quite ironically, this film earned even less than those two films, bringing in roughly $100 million less worldwide than the prior film and nearly $200 million less than the first.