This post is one of ten appearing in the series 10 Ways To Improve Your Landscape Photography. Many of us use zoom lenses and most cameras are bundled with zoom "kit" lenses. Whilst zoom lenses are highly convenient and their performance is much improved, the key downside to a zoom lens is that they make us somewhat blind to the effects of focal length.
When we start out we think the key role of focal length is to fit in as much as we can into a picture (wide angle) or to "zoom in" to make something far away bigger in our picture (telephoto). But there are many other factors that the focal length affects: the relative size and positions of objects to each other in the frame, perspective distortion, depth of field and lens distortion to name a few.
The common approach with a zoom lens is to use the zoom to make our subject fit into the frame in the way that we would like. The result of this habit is that generally we don't appreciate the effect of focal length on other elements within the image, only on how big our subject is.
It's a good practive to spend more time using a certain focal length to build up an understanding of the effects of that focal length. If you do have a zoom, you can do this by taping the zoom ring down or just forcing yourself not to touch it. It will be tricky at first but you'll build up a mental inventory of how that focal length works.
Over time you will more quickly identify what length you need for a particular scene and choose an appropriate position to suit, rather than remaining in your initial position and using the zoom to compensate. There are many benefits to this and better images result.
Having had an entirely zoom lens lineup previously I've now switched to using prime (fixed focal length) lenses almost exclusively and this has really helped me to 'see' better.