This week we talk about the Sunk cost bias, also been called the "Concorde fallacy" when the UK and French governments took their past expenses on the costly supersonic jet as a rationale for continuing the project, as opposed to cutting their losses (source: Wikipedia).

As you'll see we encounter it in every part of your life including coding and career.

We talk about various concrete examples:

- Standing in a line for too long making yourself "stand it out" because you already lost too much time. Julian fixed this the other day by setting a deadline when to cut his losses.

- Keep investing in a complicated (sub optimal) programming language while there are better ones (e.g. Python!)

- Investing more effort in a software solution with a sub optimal design. The Zen of Python offers a good criteria here: "If the implementation is hard to explain, it's a bad idea". Sometimes you need to heavily refactor, taking one step back to be able to move two steps forward.

- It also happens in one's job, by staying into a comfortable yet underappreciated role knowing you can do better elsewhere, yet you hope one day the situation will (magically) improve.

- Another good example of the sunk cost fallacy is "having to finish books", the self imposed pressure of having to read books cover to cover even if you don't like them.

- And our last example is around investing, the difficulty of cutting one's losses when money has been already invested. Ego and social pressure make this even harder.

Book about cognitive biases: Thinking, Fast and Slow by Daniel Kahneman.

CTA: take note of what is going on in your life, where your time / money / effort are going, then ask yourself if you are getting the results you want? Is it time to cut losses and move on?

And if you see a sunk cost in your Python career, maybe it's time to hop on a strategy session with us or hit us up on Slack.

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