If you expect to be successful selling stock AI images need to learn to carefully inspect for quality issues which include, of course, whether human beings are realistic. As @ricky336 noticed immediately, neither of these have realistic hands. AI is notoriously bad at rendering hands, and I'm certain that's the first place Moderators look.
Thank you for your advice. I know that it's only three fingers, but I felt it was because of the angle at which it was taken so I tried to upload it only to have it rejected due to quality issues. What about the other photo? Is there something wrong?
The doctor photo also isn't good; also three fingers. I wouldn't buy these!
Quality issues would include this!
Same reason. Still the hands. In this example, besides still looking like fingers are missing, the look as if molded from clay (the right thumb, for example).
Here is an example of AI getting hands right. Almost. I still had to clone fingernails and reshape fingers with the Liquify tool to get them looking anatomically correct. Fact is, I sometimes jokingly suggest that if one is interested in creating photorealistic people using AI, one should take some classes in anatomy to help correct AI's shortcomings.
Some suggestions. I would certainly encourage you to continue with photorealistic images of people using AI, (especially if they are in professional environments, since those are likely to sell better) but here are some additional issues to take into consideration:
Ears. If a large portion of both ears are visible, are they identical in size and shape and the intricacies involved with unique shapes inside of the outer ear itself? I often have to select and copy one ear, flip it horizontally, position it as needed, then lighten or darken it if the duplicated ear is in light or shadow.
Eyes: Are the irisis and pupils perfectly round? Usually they are not and require some Liquifying. And take care that the pupils are centered within the irises themselves. Like the ears, duplicate the best one and replace the deformed one.
Catchlights. More often than not, catchlights are identical in both eyes. If not, consider removing them and then downloading some free catchlight brushes. Are there any catchlights at all? If not, same suggestion, or just add some white dots on a new layer and adjust the brightness as necessary.
Collarbones. AI often has a habit of creating huge protruding collarbones or sharp lines in the neck. Softening them up with Gausian Blur and playing with the shadows can often help correct this issue.
Also nose, mouth, lips, handedness (two left hands), extra or missing fingers, legs, toes and botched apparel.
The other anomalies include mixed perspectives and conflicting geometry or light sources that make no sense.
There's a lot to examine & correct before AI can be submitted to Stock.