Ann by Evgeny Kuznetsov on 500px

Here's a good example of how important eye contact with the camera can be.  A model with a wandering gaze wouldn't have been able to help you produce an image this striking.

Making sure your model has strong eye contact with the camera ensures that your model also makes good eye contact with the viewer of the final image. That strong contact will draw in more viewers. I'm sure it's part of the reason you stopped to look!