It’s one of those camera techniques that you can identify as soon as you see it. Even if you didn’t know that it was called a Dolly Zoom, the unique “distancing” effect has been used time and time again throughout cinema history.
The first time it was really used to popular effect was in Alfred Hitchcock’s Vertigo. As Jimmy Stewart climbs the staircase, his mind distances himself from the floor. As the audience, we see what he sees. From then on, the technique has been used to highlight importance in subjects, emotions or scenes.
Check out this awesome supercut that proves the Dolly Zoom’s usefulness since the 1960s.