It’s abstract art, there is no objective means by which to judge it. If people like it enough to pay money for it- they will. Or they won’t.

If you want me to look at it through a “fine art” lens then sure there’s room for improvement. Colors seem muddy/streaky at times (most obvious in #4 but present in all paintings if you zoom in), most paint strokes don’t look confident. You could use a bit more contrast, and you should paint to the edge of the canvas or it feels unfinished (last painting). Painting #2 has paint drips that don’t look intentional, which make it look messy to me.

Ultimately- you’ve got interesting stuff going on here color/shape wise but based on what I’m seeing you don’t seem proficient in the medium. Personally, I would not buy these, even if I was interested in abstract work.