In my experience, men particularly tend to look to develop bodies that have a certain appeal. This can translate into a preference for big, rounded shoulders, shapely arms (particularly biceps), a V-shaped back, a big chest and a tight waist. Below the waist, big strong legs come in, with muscular glutes' sitting above them.
This can sometimes lead to dividing the body into sections and working those sections in a mechanical way until the measurements match up to the expectations of the person doing the measuring and what is seen in the mirror matches what can sometimes be seen on IG.
It is also the case, however, that certain exercises do help develop particular parts of the body and, where the arms are concerned, this Men's Health routine for the arms does the job and can be particularly useful when exercising at home.
Just don't lose sight of a whole-body aesthetic when exercising particular body parts!