What do teams get wrong about running red and purple team exercises?

A common mistake is treating the exercise as a performance event instead of a control validation process. Teams may celebrate tactics without fixing the underlying weakness, or they may stop at detection alerts without testing response quality. Another frequent error is poor scoping, which creates noise but does not meaningfully test the organisation’s likely attack paths.

Red and Purple Team Exercises Should Validate Controls, Not Perform Tactics

The main mistake is judging success by how many techniques were used or how impressive the demo looked. Red and purple team exercises are most useful when they test whether controls, detections, and response paths actually work against realistic attack paths. If the activity produces only theatre, the organisation learns little about resilience.

That means the exercise should be designed around a clear security question: what would we expect to detect, contain, or prevent if this attack path were real? A useful exercise exposes whether the control failed, whether the detection was too slow, and whether the response team can make the right decision under pressure.

Good teams treat the exercise as a validation loop, not a one-off event. They use findings to harden the environment, improve visibility, and retest the same weakness until the result changes. A strong red team finding is only valuable when it leads to an observable improvement in defensive outcome.

Why Scoping Matters More Than Coverage

Poor scope is one of the fastest ways to waste the exercise. If the test is too broad, it creates noise, distracts defenders, and produces a long list of low-value observations. If it is too narrow, it may miss the likely attack path and give false confidence.

Effective scoping starts from the organisation’s realistic exposure: key assets, material trust boundaries, and the paths an attacker would most likely try first. That keeps the exercise anchored in the environment’s actual risk profile rather than in generic technique coverage. The scope should also be explicit about what is in bounds, what is out of bounds, and which assumptions are being tested.

When teams skip this step, the result is often a technically interesting exercise that does not answer an operational question. The better standard is whether the scenario could reasonably happen, whether the defenders would recognise it, and whether the business would care about the outcome.

What Purple Teaming Is Supposed to Change

Purple teaming is often misunderstood as a reporting layer, when it should be a fast feedback mechanism between attack simulation and defence tuning. The point is not simply to observe red team activity, but to make the defensive signal better while the exercise is still relevant.

That requires defenders to validate logging, alert fidelity, triage flow, escalation criteria, and containment decisions while the scenario is fresh. It also requires the red team to be transparent enough about the technique being exercised that the blue team can improve the control, not just react to the story after the fact.

Used well, purple teaming shortens the gap between discovery and remediation. It helps teams identify whether they lack detection content, whether the response playbook is vague, or whether the control itself is structurally weak. The exercise should end with a concrete change in the defence, not just a retrospective.

Risk and Threat Considerations

Badly run exercises can create a false sense of security, especially when leadership hears “we were not detected” without understanding the scope or the test conditions. They can also consume time and attention without reducing exposure if the findings are not translated into control improvements. For deeper guidance on defence validation and response coordination, teams often anchor their programmes in FIRST standards and map the simulated behaviour to established adversary techniques such as MITRE ATT&CK Enterprise Matrix.

Failure mechanism: The exercise is framed as a performance test, so teams optimise for visible tactics instead of validating the control that should stop, detect, or contain them. When scope is poor, the test can miss the attack path that actually matters or generate noise that defenders cannot act on.

Impact: The organisation may approve weak controls, underinvest in remediation, or believe it has tested a path that it has only rehearsed. In the worst case, an untested weakness survives into production because the exercise measured activity, not defensive outcome.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

MITRE ATT&CK addresses the attack and risk surface, while NIST CSF 2.0 and CIS Controls v8 set the governance and control requirements practitioners need to meet.

Framework	Control / Reference	Relevance
MITRE ATT&CK	Enterprise Matrix	Maps simulated attack paths to adversary techniques used in red team exercises.
Recommendation — Map exercise scenarios to ATT&CK techniques and use the gaps to tune detections and response.
NIST CSF 2.0	DE.CM-01 — Monitoring for Anomalies, Events, and Indicators	Red and purple teams validate whether monitoring actually sees the simulated attack path.
	RS.CO-02 — Incident Response Plan Execution	Exercises should prove the organisation can execute response decisions under realistic conditions.
	GV.RR-01 — Roles, Responsibilities, and Authorities are Established and Communicated	Purple teaming depends on clear ownership for findings, remediation, and retest follow-through.
Recommendation — Test monitoring coverage against the exercised path and close visibility gaps. Run the exercise against response playbooks and fix decision and escalation failures. Assign clear owners for findings, remediation, and retest before the exercise starts.
CIS Controls v8	CIS-17 — Incident Response Management	Red and purple team outcomes should improve incident handling, not just enumerate tactics.
Recommendation — Use exercise results to harden incident handling and validate response procedures.

Practitioner Guidance

What to prioritise: Define the exercise around one or two high-value attack paths and the specific defensive outcomes you expect to observe. If the team cannot say what “good” detection or response looks like before the test starts, the exercise is already too vague.

What to verify: Confirm that the exercise will produce evidence the organisation can act on, such as alert quality, triage decisions, containment timing, and the exact control gap that needs repair. Use a replay or retest only after the remediation has been implemented, otherwise you are just repeating the same failure.

Common mistake: Treating a successful red team run as a success for security. The real success is when the environment changes because the exercise exposed something meaningful and the next test shows improvement.

Practitioner takeaway: The best red and purple team work is measured by whether it changes defensive behaviour, not by whether the scenario looked sophisticated.