More sharp detail is visible.
For example, a 28mm lens has the ability to capture more of the picture in sharp focus than a 100mm lens. Therefore, you need not worry as much about a distant subject being out of focus. You can use this to keep either the foreground or background out of focus while maintaining the subject in focus. When changing the aperture setting, you will need to also adjust the shutter to maintain the correct exposure. An example is shown below.