Never overestimate your abilities - the "Dunning-Kruger" effect

The Dunning–Kruger effect is often mentioned in diving, sometimes too casually. It is tempting to use it as a label for somebody we think is overconfident. I find it more useful as a question to ask about ourselves: what am I not seeing because I do not yet have enough experience to recognise it?

Confidence and competence do not always grow together

A diver can feel comfortable long before they have experienced enough variation to understand where their limits really are. Calm water, good visibility and familiar equipment can make a series of dives feel easy. Change the current, visibility, temperature, entry, team or task loading and the same diver may suddenly have much less spare capacity.

The opposite can happen as well. More experienced divers often become more aware of what can go wrong, which can make their language sound less absolute rather than more.

Diving gives us plenty of places to fool ourselves

Buoyancy, navigation, gas planning, rescue skills, wreck penetration, current and equipment configuration can all feel straightforward when nothing unusual happens. The test is not whether a skill worked once. It is whether you can recognise when the situation is changing and still perform it when part of your attention is occupied elsewhere.

This is one reason I dislike using depth or certification level as a shortcut for experience. A diver may have many dives in one environment and very little experience in another.

Do not use the idea as an insult

Calling another diver “Dunning–Kruger” does not make anybody safer. It usually ends the useful part of the conversation. A better approach is to ask what evidence supports a decision: training, recent practice, conditions, gas, redundancy, previous exposure to the environment and a realistic exit plan.

Practical ways to keep confidence honest

• Debrief dives, including the ones that went well.
• Ask for feedback from people you trust, especially when they see something you cannot see yourself.
• Separate “I have done this before” from “I can manage it today, in these conditions, with this team and this equipment”.
• Keep basic skills current instead of assuming an old certification keeps them current for you.
• Be willing to change or cancel a dive without treating that decision as failure.

Experience should not make a diver certain about everything. If anything, it should make the difference between what we know, what we assume and what we still need to verify much clearer.