Human in the Loop
Put review where a person can actually detect and prevent the important error. · AI Product Management · Lesson 52 · 3 min
Human in the Loop · 3 min
Situation
Every output is “reviewed,” but mistakes still pass.
A model drafts customer account changes. Reviewers see a long queue and click Approve quickly. The team treats human review as a safety guarantee.
A person in the workflow helps only if they have the information, time, competence, and authority to evaluate the action.
Mental model
Review has a job and a location.
A human can review a draft, approve an action, handle an exception, or resolve an escalation. These are different responsibilities.
Place review before the consequential boundary when prevention matters. Reviewing an automatically sent email afterward can support learning, but it cannot unsend the message.
Example
Make the decision inspectable.
For an account change, show the current state, proposed change, supporting evidence, affected resources, and consequence. Let the reviewer edit, reject, or request clarification.
Avoid presenting only the model's confident summary. Reviewers need access to the evidence that could contradict it, especially on ambiguous cases.
Failure case
Review cost erases the benefit.
If checking a draft takes longer than doing the task directly, the feature may not save time. If the queue is too large, delays can make the product unusable.
Measure review time, disagreement, missed errors, and queue age. Include those costs in the product's economics and service expectations.
PM decision
Route exceptions deliberately.
Use validated signals and task rules to decide which cases need review. High-impact actions may require review regardless of model confidence. Routine reversible drafts may need lighter oversight.
Define escalation ownership and a fallback if nobody responds. Human review without capacity is a dependency the product cannot reliably satisfy.
Remember this
A human is a designed part of the system.
Make review meaningful, timely, and informed. Evaluate whether it catches the errors that matter rather than counting how many approvals occurred.