During our recent vacation, we had some nice walks in the Swedish woods. A while ago, I bought my wife a fancy iPod with an included step counter (and all kind of other fancy ‘health’ functions and statistics). She took this device when we went for a walk, just for fun to see how far it would be around the lake and that kind of things.

At one point, my wife mentioned that she recently had seen a news item as well as a scientific article that mentioned research which had ‘shown’ that step counters and similar devices did not work if you wanted to less weight.

The article tells us that “Devices that monitor and provide feedback on physical activity may not offer an advantage over standard behavioral weight loss approaches”.

That is interesting, because it sounds really counter-intuitive at first. Besides, has other research not ‘found’ the opposite? But then, this is a rather typical phenomenon that you can find research and sources that shows different results. All the more reason to look critically at the sources and methods to find out what the research or source really is worth.

But that was not what I wanted to discuss at this point. Let us assume that the recent research is right and that these activity-tracking devices indeed do not help as we assume they should do. What the article does not mention is why that would be so. Here is my hypothesis:

I am fairly sure that we are dealing with a typical example of the means becoming the goal. Someone has at some point come with some advisable number of steps that one should go a day in order to stay healthy or lose weight. 10.000 is a typical number - what a coincidence that it would be such a nice round one (one would expect something more differentiated - also TNO makes some critical remarks). But whatever…

Assuming that 10.000 it is, what happens is that many people replace their original goal (getting healthier, losing some weight, getting in better shape) with reaching the numerical goal (go 10.000 steps, that is what the doctor said) without any regard if the real goal is reached. It is a rather typical effect of the System 1 and 2 substitution of a difficult question with a simpler, alike sounding version.

There may also be an adverse effect of bonuses at play, because many people promise themselves some kind motivating incentive (“If I go 10.000 steps today, I can eat a bag of potato chips before the telly tonight”). By that, the positive effect can be ruined by the unintended side-effects of the measure/bonus.

Of course, this is no exclusive thing for weight watchers. In fact, many KPIs have exactly this effect. Numerical goals tend to become an end in themselves, which leads to unwanted effects, like when responsible managers manage quantity, not quality.

When something becomes a numerical target, the target is easily separated from what it intends to achieve. Set a number of near-miss reports and incentivise reporting: you can be rather sure that you get the desired number of reports, not necessarily the quality of reporting or wanted improvement. Hopkins and Maslen say in their book “Risky Rewards” that this is not necessarily dishonest; it is merely the most practical way for busy people to ensure that they meet their targets. But dishonest or not, it undermines the value of the activity entirely.

So, you can manage what you measure, but very often it does not help you one tiny bit when you forget the real objectives that are behind that number and do not pay attention to unintended side-effects from your metrics and bonuses.


Also published on Linkedin.