This is the part that most photographers miss when getting into Fashion. There is no doubt that this is a perfect photo. It is shot 100% dead on. Color is great and the model is stunning. The backdrop works well.
Here is where you become pro. She is in a "short dress" pose but wearing a long dress. To photograph a model, you not only need to know your job but the model's job as well.
I won't pick apart another's work but I can tell you, looking at this shot for a few moments before taking the photo, you would have seen that her arm is bending too far and even if this pose would work with this dress, her hand is too relaxed and her face is not emotional enough to get the point across.
These are not photography errors. This is having all of the wonderful resources to take an outstanding photo, and not thinking deep enough into the shot.
FYI - I am guilty of this 90 percent of the time and the only solution is to slow down and spend more time on the set up.