I find it remarkable how much my 3-year-old son – and presumably by extension most kids his age – go crazy for stickers. They don’t do anything, besides stick to a wall-chart. They don’t even necessarily have to lead to any better reward (10 stickers and we buy you a toy, etc.). It’s a completely false economy, and yet kids will modify their behaviour just to obtain stickers from their parents.

I started to wonder what age we grow out of that, and start to realise that the reward is so near zero that we’re effectively being tricked by our parents into behaving well for no reward.

My conclusion is “never”.

Here is the sticker chart on my wall. Players of Foursquare and its rivals modify their behaviour – to give a company a complete list of their location history so that they can use it for marketing purposes. In return, for each ever more excessive level of location-sharing, you get a sticker on your wall-chart. And not even a real sticker, just a 100×100 JPEG representing your achievement.

The only reason Foursquare badges appeal to grown-ups and wall-charts in our bedrooms don’t is that Foursquare is public and social – we can compare our badges with others’, and strive to have the most.

We never grow out of wanting a sticker. We just compound it with pride, greed, and the desire to be better than everyone else. Isn’t that worse?