Shooting with a camera is like shooting with a gun. If you keep firing your gun, you are bound to eventually hit the bulls' eye. It may take innumerable shots, but you'll eventually get it. The same goes with a camera. Just keep shooting. As you get better with practice, you need less images to get a successful hit. A true expert may need just a few shots to get a great image. At the moment I still need hundreds.
The other secret is with the model. Most people are attracted by the picture because the girl has a beautiful face. Replace that with a less attractive face, using the same pose, you will not visualize it as a cover shot.
Finally, the pose. In my opinion, a truly accomplished portrait photographer is able to pose the model with seemingly little effort. A maestro portrait photographer is a delight to watch. As he speaks to the model, he is actually easing her into projecting her best self, in the best light (pun intended). "The Shot" was an exceptional piece of work (I'll gladly agree to that); the photographer is, but still work-in-progress!