The light problem
The highest-voted answer names the specific mistake: the sun directly behind the photographer, which old film packaging used to recommend and which is close to the worst option most of the time. A camera has one eye, so it needs shadow playing against light to give things form. Move the light round to the side and the same subject acquires edges, texture and volume — none of which existed in the flat-lit version.
The question to ask before pressing the shutter
The second answer supplies what is probably the more useful half: what are you actually trying to show? If the photographer cannot say whether the subject is the mountains, the ship or the sky, the viewer will not work it out either, and the result reads as pointless rather than wrong. A view impresses in person partly because you are standing in it. A photograph only gets the frame, so the frame has to be about something.
What people suggested doing differently
- Move. Several answers pointed out the picture was taken from where the photographer happened to be standing — a road — rather than from a position chosen for the picture.
- Use angle and perspective deliberately, since they are what communicate scale and distance in a flat image.
- Put something in the foreground so the eye has a route into the depth of the scene.
- Crop away everything that does not contribute. One answer treated this as the fastest available improvement.
- Learn the exposure controls properly. One reply put it bluntly: shooting on full automatic makes the camera an expensive compact.
The honest caveat
- Some of this is recoverable afterwards — contrast, brightness, cropping — and the thread said so.
- The light and the position are not. Those are decided when you are standing there, which is why the advice is mostly about the moment rather than the edit.
- The specific camera involved is irrelevant to every answer given, which is itself the point.