You need more than mistakes to learn

- english debrief decision-making gareth lock psychological safety teamwork Jul 02, 2023


 There are plenty of quotes out there relating to learning from mistakes.

  • "Experience is simply the name we give our mistakes." - Oscar Wilde
  • "You must learn from the mistakes of others. You can't possibly live long enough to make them all yourself." - Samuel Levenson
  • "Making mistakes simply means you are learning faster." - Weston H. Agor
  • "Mishaps are like knives, that either serve us or cut us, as we grasp them by the blade or the handle." - James Russell Lowell
  • "Take chances, make mistakes. That's how you grow. Pain nourishes your courage. You have to fail in order to practice being brave." - Mary Tyler Moore
  • "Mistakes are the portals of discovery." - James Joyce
  • "It's fine to celebrate success, but it is more important to heed the lessons of failure." - Bill Gates
  • "Your mistake does not define who you are… you are your possibilities." - Oprah Winfrey

The thing is that it isn’t the mistake that we learn from, it is the reflection on the mistake (activity) that is important. In a previous blog, I wrote about the difficulty in learning from near-misses, especially if there was a successful outcome. We don’t have a tendency to look back at how it made sense for us to do what we did. We don’t look for the error-producing conditions that preceded the event, primarily focusing on the outcomes, saying we wouldn’t do that again. 

This isn’t helped by the way our brains work. We have a bias called the outcome bias which leads us to judge the quality of the outcomes rather than the quality of the decision which led to the outcome. This applies to successful outcomes as well as adverse events. The more severe the outcome (when it comes to an adverse event), the harsher we judge the ‘poor’ decision which led to the outcome, even though we rarely explore the decision-making of those involved and how it made sense.


In the diving domain, we have formal incident reports from organisations like Divers Alert Network and the British Sub Aqua Club. These are really good sources of information concerning incidents and accidents. One of the limitations is the context surrounding the event and how they are classified. For example, an event might be categorised as a DCS event. However, the DCS was caused by a rapid ascent, following an out-of-gas situation caused by distractions and inadequate gas planning and a team separation. If the report outputs are going to be used for trending incidents, the learning should be focused on the contributory factors and not just the outcomes. Note, these are contributory factors rather than causal ones. In many cases, the causal factors are present in dives that don’t have an adverse outcome.


Learning doesn’t happen without change

One of the hardest parts about learning is the change that is needed. I remember a quote from a senior Army officer about the difference between a lesson identified and a lesson learned. A lesson learned either means the current situation has been consciously accepted as a risk and so we will carry on with the status quo, or that a change has been put in place and its effect has been measured. Otherwise, it is just a lesson identified. There are many more lessons identified than lessons learned.

As an example, I was involved in a major review of diving safety within an organisation. There were many recommendations made. The responsible and accountable individual would not close off the recommendations until something had been put in place and its effect had been shown to align with the recommendations. They knew the difference between lessons identified and lessons learned.


In diving, we might recognise that our buoyancy isn’t great, but do we set aside dives to work on it, maybe paying for a day’s coaching with an instructor? We might notice that our trim and fin kicking aren’t where they should be because we silt out the bottom and reduce visibility. We might recognise that as an instructor we aren’t very good at communicating with our students, but do we spend time speaking with our students about where the communication is missing? What about recognising we have reduced situation awareness because we missed a critical signal or activity on diving? Saying ‘pay more attention’ isn’t going to help because we have a finite capacity, what we need to look at where our attention was pointing and why was that considered more important. It could be that our attention was pointing at core diving skills e.g., buoyancy and trim or secondary skills e.g., photography or line laying, and so they need to be developed.

All of the above need us to reflect on the activity. That can be done via a comprehensive post-dive debrief like the one contained here, or a simple one which asks four questions:

  • What did I/we do well?
  • Why did it go well?
  • What do I/we need to improve on?
  • How will we make that improvement?

The why and how questions are the most important. Observations are relatively easy, but it takes more effort to consider ‘why’ it went well, or ‘how’ the improvement will be made. If you want to improve, you must also focus on specifics, not generalities. Saying ‘communications’ or ‘teamwork’ was good (or needs improvement) isn’t going to help going forward. Examples of this are below:

  • “The closed-loop communications worked when you checked that I was okay before we entered the wreck and you waited for a response before proceeding.”
  • “Thanks for helping out when I managed to cross-clip the bolt snap on the left hip D-ring. You told me to hold, so I just stayed there until you told me I could move again.”
  • “Teamwork broke down right from the start because we weren’t clear on our roles before we entered the water. This caused confusion when we got to the survey site. The briefing format we have doesn’t explicitly cover that, and we will change that before we brief the next dive.”



Not all errors are the same

Mistakes, slips, and lapses are all particular types of errors. All of them are difficult to spot in the flow, and therefore we need something to happen to pick them up.

  • A mistake is doing something wrong, thinking you’re doing it right e.g., putting up a dSMB and getting entangled in the line, not being able to maintain a stop accurately, or assembling gear incorrectly.
  • A slip is an execution error e.g., cross-clip a bolt snap, putting the wrong date on a gas analysis sticker, or putting the deco stage on the wrong side (if you’re using rich right/lean left).
  • A lapse is a memory error, where we’ve forgotten something.

In each of the above cases, without reflection surrounding the event, we could easily say ‘do it right next time’, ‘be more careful’, or ‘need to remember that’, but there will be context surrounding why action was not carried out correctly. We cannot learn from an ‘error’ if don’t understand how it developed and what needs to practically be done. Therefore, we need to look at the conditions, not the outcomes.


Psychological Safety and Just Culture

Finally, we need to consider the social environment and how easy it is to talk about the mistakes we make, so that others can help us learn, and you can help them learn. This series of four blogs looks at the different stages of psychological safety in a team – stage two is learner safety which is where we know it is okay to make a mistake. Team members look for learner safety before they start to push their learning boundaries and look to improve. Improvement nearly always means making errors…

A Just Culture is a retrospective approach to something that has gone wrong and the need to look at how it made sense for those involved. This video explains a little more about this topic.



Learning from errors is not easy. We might think that saying ‘pay more attention’ or ‘be more careful’ or ‘follow the checklist’ will improve things, but if we don’t understand the context surrounding the event, then we are unlikely to improve. That doesn't mean things won't change, but it will be slower than making a positive attempt to reflect and learn. Learning is about change, and change is hard for a whole bunch of social, cognitive, and technical reasons!! The first step is recognising that you might not be helping your learning if you don’t reflect on the context because you are focusing on the outcome.

Gareth Lock is the owner of The Human Diver, a niche company focused on educating and developing divers, instructors and related teams to be high-performing. If you'd like to deepen your diving experience, consider taking the online introduction course which will change your attitude towards diving because safety is your perception, visit the website.