Judges
What changes when a person does the rating
Not a question of which is better. They answer different questions, and most disappointment comes from asking one of them for the other one's answer.
An algorithm and a person given the same photograph produce two things that look superficially similar - an assessment, some commentary, often a number - and are not remotely the same product.
Being clear about the difference before you commission anything is the single best predictor of being happy with what arrives.
What the algorithm is good at
Consistency. The same input returns close to the same output. It does not get tired, generous at the end of a session, or influenced by the previous submission.
Impersonality. It does not know who you are and cannot be embarrassed. For a lot of people that is the entire appeal.
Speed and price. Minutes, and a price on the card before you commit.
Comparability. Because it is consistent, scoring several of your own photos on one system produces a meaningful ranking. That is a real analytical tool.
What a person is good at
Responding to you specifically. This is the whole difference and it is not a small one. You write what you want; what comes back answers it. An algorithm generates from a template and cannot do otherwise, however well the template is tuned.
Register. Encouraging, blunt, degrading, clinical, affectionate - a person who does one of these well does it in a way a tone setting approximates rather than achieves. Most people commissioning a human review are buying the register, not the assessment.
Judgement about what you actually asked for. Requests are frequently a bit off from what the person wanted, and a good judge reads through to the intent. Nothing automated does this.
Presence. Someone looked. For most buyers this is the point, and it is not a thing an algorithm can supply at any price, because its absence is definitional rather than a limitation.
What neither is good at
Telling you something true about yourself. One is a model's read of an image, the other is one person's opinion. Both are entertainment, and treating either as a verdict is a way to have a worse time with it than it was designed to give you.
Which to ask for
Want a number you can compare against other numbers? That is the algorithm's job, and it does it better.
Want a specific person to respond to a specific thing in a specific register? No amount of model quality substitutes.
Worth being honest with yourself at this point, because what people are actually buying is usually not the assessment - and the ones who work that out before ordering are reliably the ones who come away happy.
If you are weighing the two as a purchase - price, wait, what you get - Cock Rate has written that comparison directly, which is a more useful place to start than anything general.
If you have decided on a person, the next questions are practical: what actually arrives, how it gets priced, and how to ask for it well. The last one changes the result more than most people expect.