Common warning signs include repeated password resets, failed sign-in attempts, OTP delivery problems, slow transaction completion, and rising support workload around authentication. If users struggle to access signing flows or abandon transactions because the login step is clumsy, the authentication model is creating avoidable operational friction and measurable security exposure.
When the authentication layer is becoming the bottleneck
The strongest sign that traditional signer authentication is past its useful life is not a single outage, it is a pattern. Repeated password resets, OTP failures, sign-in retries, and users abandoning transactions all indicate that the control is adding friction without adding proportionate trust. At that point, authentication is no longer just a gate, it is a measurable source of operational drag and avoidable risk.
That friction often shows up most clearly in signing workflows because the user expectation is simple: complete the transaction quickly and with clear assurance. When the login step repeatedly interrupts that path, teams usually compensate with shortcuts, exception handling, or support overrides. Those compensations are a warning sign in their own right, because they often create a weaker control than the one they were meant to replace.
- Failed sign-ins are increasing instead of staying rare and explainable.
- Users are repeatedly resetting passwords or requesting token reissues.
- OTP delivery is unreliable, slow, or inconsistent across devices and regions.
- Signing latency is high enough that users abandon the flow.
- Help desk demand around access is rising faster than transaction volume.
In practice, the issue is not only usability. When authentication is brittle, organisations tend to see more recovery steps, more manual approvals, and more exceptions, which enlarges the attack surface. A model that depends on frequent human intervention is harder to secure consistently than one that is both stronger and less disruptive.
What the warning signs are really telling you
Those symptoms usually mean the current authentication model no longer matches the risk profile or the user journey. The signer population may be growing, transaction urgency may be higher, or the organisation may have outgrown a control that was acceptable when usage was light and access patterns were predictable. The signal is strongest when failures cluster around the same few points, such as OTP delivery, password recovery, or step-up prompts that are triggered too often.
There is also a governance signal hidden in the support burden. If authentication problems are becoming a recurring service desk category, then the control is no longer self-service and reliable enough to serve as a primary access mechanism. In regulated or high-value signing flows, that matters because every extra exception path must still preserve assurance, traceability, and revocation discipline. NHIMG’s Ultimate Guide to NHIs is useful here because the same lifecycle and visibility problems that affect machine identities often show up when access controls rely on brittle credentials and weak operational hygiene.
For a broader control view, the issue aligns with access control and identification guidance in NIST SP 800-53 Rev 5 Security and Privacy Controls, especially where authentication quality, auditability, and access enforcement need to be dependable under normal load. It also fits the implementation focus of OWASP Cheat Sheet Series, which is useful when the question is how to reduce authentication friction without weakening the control itself.
Practitioner guidance for deciding when to replace the model
What to verify: Separate occasional user error from structural failure. If the same users, devices, geographies, or signing steps repeatedly generate resets, OTP problems, or abandoned sessions, treat that as a design issue rather than a training issue.
Decision rule: If the authentication step is causing measurable transaction drop-off, recurring support intervention, or exception handling that bypasses normal assurance, it is no longer fit for purpose and should be redesigned before it is scaled further.
What good looks like: Sign-in becomes low-friction without becoming low-trust. Users complete signing with fewer retries, support volume falls, and recovery or fallback paths are rare, tightly governed, and fully observable.
Practitioner takeaway: The right test is not whether the authentication control exists, it is whether it still produces dependable assurance at the point of signing without forcing users or operators into workarounds.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
NIST CSF 2.0, CIS Controls v8 and NIST SP 800-63 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | PR.AC-7 — Identity Management, Authentication and Access Control | Authentication friction and assurance directly affect access control quality. |
| GV.RM-03 — Risk Appetite and Risk Tolerance | Repeated sign-in failures signal operational and security risk that should be judged against tolerance. | |
| Recommendation — Tune authentication to preserve strong assurance without creating avoidable user friction. Set a threshold for authentication failure, then replace controls that exceed it. | ||
| CIS Controls v8 | 5.1 — Establish and Maintain an Inventory of Accounts | Frequent resets and support exceptions often reveal account lifecycle and access hygiene weaknesses. |
| Recommendation — Review account lifecycle hygiene when sign-in issues become repetitive. | ||
| NIST SP 800-63 | AAL — Authentication Assurance Level | The question is fundamentally about when the current signer authentication no longer delivers sufficient assurance. |
| Recommendation — Match the assurance level to the transaction risk and replace brittle login steps. | ||
Related resources from NHI Mgmt Group
- What are the signs that an SMS OTP model is no longer fit for purpose?
- What are the signs that traditional user authentication is no longer enough against identity fraud?
- What are the signs that legacy authentication is no longer fit for digital identity programmes?
- What are the signs that legacy GRC software is no longer fit for purpose?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 17, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
