Eiffel Over

Tag: DesignDecisions

  • Beware of sunk-cost fallacy

    I suffer from sunk-cost fallacy. This is the phenomenon whereby you remain committed to a previous choice because of what you have ’sunk’ or invested in it, even though new evidence suggests a different option would cost you less.

    It shows up for me when I have made a plan to do something, and then plans change, for example when travelling or making plans for the weekend. I remain psychologically committed to the original plan even though it might not make sense any more. I suffer from sunk-cost fallacy because I am a human, and this is a common bias that we suffer. 

    Sunk-cost fallacy also shows up in design. It is when we remain committed to one option which we have invested time, resource and psychological energy in, even when a better answer emerges. If our priority is to get our job done, then making decisions purely on the basis of sunk costs might be sensible. But if our priority is getting the right design, then the sunk-cost is a poor guide, as it fails to account for the total cost of having the wrong answer. 

    Where money is concerned the distraction is how much you have already spent, when the real concern should be how much you still have to spend. For major projects, where we routinely, systematically underestimate the future costs, the risk of sunk-cost fallacy affecting judgement is even greater. 

    Whether we are making plans for the weekend or plans for a new railway, look out for sunk-cost fallacy!

  • The past, present and future at the same time

    This post has moved.
    It now lives on the Constructivist blog: read the updated version →

    Eiffel Over is now my stage for engineering-related clowning, singing, dancing and writing — you’ll find my professional writing on design and regenerative thinking over at Constructivist.

    In conversations about regenerative design I draw heavily on Bill Sharpe’s Three-Horizons Model because it allows us to make sense of a complex situation. For in any group of people collaborating on a project it is possible to find people who are managing the decisions of the past, some who are dreaming about the future and some who are thinking about what we should do next. 

    This co-existence of past, present and future so beautifully showed up for me recently as a parent, watching our daughter manage the transitions of the present, dreaming about her grown-up plans for the future, and still wanting the care of a younger self. 

    And now I am thinking about it, I recognise these different voices, with needs and hopes, from different times, co-exist in my adult head too.

    The power I see in Bill’s teaching is to recognise and welcome all three of these voices at the same time. Last week I wrote about chaos and looking for the signal in the noise. But when we can start to recognise that there are three (or more) things going when we encounter any change, we can start to make more sense of the signals we are working with. 

    The future, present and the past are always present. Recognising them can help us work with them to reach design decisions that are the best next step.