Humans in this space tend to make mistakes like, "Added rent as per-square-foot instead of absolute value," or, "Missed a rent escalation for year 3."
These tend to be easy to catch, even for the same person who's reviewing the data. They would see that rent steps looked strange (Y2 and Y4, but not Y3) or there was an order-of-magnitude difference in rent from one month to another.
AI can do something like invent reasonable-looking rent steps. They're designed to create output that seems reasonable, even if it's completely made up.
When humans are wrong, they tend to misread what's there, which is much less insidious than inventing something.
And if you have a human reviewer for all the work this AI does, what's the point of the AI in the first place? The human has become the source of truth either way.