Sometimes photos have distortion and perspective issues. You can get barrel distortion from wideangle lenses and perspective distortion from converging verticals. These are actually two separate things, and while Affinity Photo has lens-correction profiles which can fix lens distortion, any kind of perspective distortion is something you have to fix yourself.
Perspective distortion is caused when you tilt the camera upwards to capture the full height of a tall building, for example, and is more prominent with wideangle lenses
