They fail because the reviewer is the control. When managers face too many entitlements, too little context, or unclear accountability, they often approve everything to clear the queue. That removes scrutiny from least privilege decisions and turns access certification into a formality. The result is weaker access control, higher unauthorized access risk, and more audit exposure.
Why This Matters for Security Teams
user access review are supposed to be a compensating control for entitlement drift, privilege creep, and exceptions that never got cleaned up. In practice, the control often depends on a reviewer who does not have enough time, system context, or ownership clarity to make a defensible decision. That is why the process can quietly become a checkbox exercise instead of a meaningful least-privilege check.
This matters because access review fatigue is not a theoretical issue. It shows up when managers are asked to certify dozens or hundreds of entitlements across systems they do not actively administer. The result is predictable: approvals become default behaviour, and revocation gets delayed until an audit, incident, or data exposure forces action. NHI Management Group’s Ultimate Guide to NHIs — Regulatory and Audit Perspectives frames this as an audit and governance failure, not just an operational inconvenience.
Security teams often miss that the reviewer is effectively the control. If the reviewer cannot distinguish legitimate access from stale access, the certification has little evidentiary value. In practice, many security teams encounter bad access hygiene only after an audit finding or incident has already exposed how little scrutiny the review process actually produced.
How It Works in Practice
Access reviews fail when the organization expects human judgment to compensate for poor entitlement design. Managers are asked to decide on access they did not grant, do not use, and may not understand. Under those conditions, the review tends to optimize for speed and closure, not accuracy. NIST’s Cybersecurity Framework 2.0 reinforces that governance and continuous oversight must be built into the operating model, not bolted on at review time.
Effective review programs reduce the reviewer burden before the certification window opens. That usually means:
- Grouping entitlements by business function, application, or risk tier so reviewers assess patterns instead of raw line items.
- Providing context such as last use, privilege level, data sensitivity, and whether access was approved through JIT or exception workflows.
- Routing privileged or high-risk access to system owners or security approvers, not only line managers.
- Automatically flagging dormant, duplicate, and out-of-role access for removal rather than asking reviewers to discover it manually.
- Using policy-driven thresholds so low-risk access can be auto-approved only when conditions are explicit and documented.
This is where the broader NHI governance lesson becomes relevant. The Top 10 NHI Issues highlights that identity sprawl and weak lifecycle control create review noise, which is equally true for user entitlements and non-human access. OWASP’s Non-Human Identity Top 10 similarly treats unmanaged access as a control failure, because review cannot compensate for poor identity hygiene upstream. Organisations also need a realistic volume model: one reason reviews become unmanageable is that entitlements accumulate faster than teams can validate them. These controls tend to break down in fast-growing environments with frequent role changes and shared application ownership because the reviewer lacks reliable context at the moment of certification.
Common Variations and Edge Cases
Tighter review requirements often increase operational overhead, so organisations have to balance assurance against reviewer fatigue and business disruption. There is no universal standard for this yet, but current guidance suggests that high-risk access should receive deeper scrutiny while low-risk access should be reviewed through lighter, automated checks.
Manager overload is not the only failure mode. Reviews also break down when access is inherited through nested groups, when entitlements are tied to outsourced teams, or when the person signing off has no direct visibility into the application owner’s privilege model. In those cases, the correct reviewer may be a system owner, data owner, or delegated approver with actual operational knowledge. NHI Management Group’s Ultimate Guide to NHIs — Lifecycle Processes for Managing NHIs is useful here because it shows why lifecycle state matters more than annual point-in-time certification.
One practical benchmark comes from NHIMG research on secrets governance: the average estimated time to remediate a leaked secret is 27 days, despite 75% of organisations expressing strong confidence in their secrets management capabilities. That gap mirrors access review programs, where confidence in the process is often much higher than the actual quality of decisions. The control works only when review is backed by clear ownership, clean entitlement data, and removal automation. Otherwise, it becomes a record that someone clicked approve.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 and CSA MAESTRO address the attack and risk surface, while NIST CSF 2.0, NIST SP 800-53 Rev 5 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-01 | Access review noise often comes from poor non-human entitlement hygiene and stale access paths. |
| NIST CSF 2.0 | PR.AA-01 | Identity and access assurance depends on reliable review and accountability processes. |
| NIST SP 800-53 Rev 5 | AC-6 | Least privilege is the core control harmed when overloaded reviewers approve excess access. |
| NIST AI RMF | The governance function applies to accountability and oversight for identity review decisions. | |
| CSA MAESTRO | Governance for autonomous or delegated access requires ownership, policy, and runtime oversight. |
Audit privileged and dormant access against least-privilege rules and remove unjustified entitlements.
Related resources from NHI Mgmt Group
- Why do user access reviews fail when managers rely on spreadsheets and raw entitlement lists?
- Why do user access reviews often fail to improve security in practice?
- Who should be accountable for user access reviews in a regulated environment?
- How should security teams run user access reviews for high-risk systems and cloud environments?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on August 27, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
