Cognitive effort – choosing, calculating, attending, applying will power etc – is a limited resource, and it tires like a muscle tires. This is called Decision Fatigue.
It has been shown that, for example:
- after making a complicated mathematical calculation people will be more likely to to choose cake over fruit than those having to do a simple calculation – their will power is depleted; and
- doctors are more likely to prescribe antibiotics later in the day than first thing – they take the easy path.
A key way that Nudge operates is to reduce the cognitive effort to making it easy to choose. The idea is to create defaults where an individual can ‘choose not to choose’ by taking the path of least resistance. If it is a good default, then we expend less effort, and experience less decision fatigue.
Good design in the real world. can make it easy for us to choose and reduce our decision fatigue. I’m writing this because I saw the painted footprints on this escalator yesterday coming out of the underground into St Pancras .
It’s interesting to contemplate that when we are designing, it’s the choice points we need to design to be easy. It’s the ‘obviousness’, the affordance, that is the important thing. Easy to choose over easy to use.