In a presentation, portfolio, or collection, many things are taken into consideration. For starters, design- if it’s functional, practical, etc. Patterns with lines, shapes, etc. are also searched for. Style is important as well, but there still needs to be variety.
Presenting and sharing artworks shapes ideas, beliefs and experiences, because art is influential. Every artist can tell you they’ve been influenced by a piece or an artist, whether it be to try something new or work on something specific. Maybe they liked how an artist chose to do something, and would incorporate that technique in their work. Maybe they liked what the subject the artist chose and decided to try it out for themselves.
Criticizing art is a way of learning from it. Seeing errors, mistakes, etc. can help you learn from those faults and how to avoid them. It can also show you what was done correctly, and maybe you could learn in a positive way from how it was done.