When you look at the two photos above, which one feels more memorable to you?
The main difference might be the sense of excitement you draw from watching the person on the right interact with the landscape versus observing the mountain on the left by itself.
A couple years ago, an MIT study found that adding people to photos actually makes images more memorable. For me, seeing a person in an image makes it more memorable because it tells a greater story than a landscape ever could.
It also adds cultural reference.
This beach scene, for example, could have been taken anywhere in the world. Unless I were to tell you where it was taken, you'd have no indicator. Adding a person, as in this shot, provides clues and a flare of excitement. This picture was staged, by the way. I chose the background because of the beautiful light, then invited this local over, asking him to jump for me.
Adding a person to a photo also creates scale and context when placed next to a building.
So, next time you are out in the field consider making the bold move and asking someone to just stand in your photo or set up the shot and wait for something to happen.