Photoshop is fun to use because we can combine certain elements to create an unique concept, that can look convincing to even the most experienced set of eyes. You can get as creative with your photo manipulation works since the aim is to achieve a realistic view of an unreal picture. The thing with Photoshop is that when done accurately produces great results and when not it leads to funny results.
Here is one such image where Photoshop went wrong!
The model seems to have two right feet which is obviously against nature's law. Photoshop fails, we laugh.