The Wiki Man

A lesson in decision-making from the world’s worst road sign

It’s cognitive bias that makes me blame myself for missing the M25

28 March 2015

9:00 AM

28 March 2015

9:00 AM

Driving from Dover on the M20 a year ago I missed the turning for the M25. A month later I did it again. Then again. ‘You bloody idiot — you missed the turning,’ I said to myself each time. Eventually, after I had missed the turning five times in ten journeys, I wondered if it was really all my fault. So I logged on to Google Street View and retraced the stretch of the M20 leading up to the junction. That’s when I found the image below.

Perhaps it doesn’t look odd to you. It took me a while to spot why it is a contender for the world’s worst road sign. By the time you can read the information it contains, you can no longer act on it. Some idiot has painted a row of chevrons in the road for the previous 500 yards (which it is illegal to cross). So the sign announces your lane too late for you to do anything about it. As Bob Dylan explains in ‘Brownsville Girl’ (though he is possibly not referring to the M20), ‘I’ve always been the kind of person that doesn’t like to trespass/ but sometimes you just find yourself over the line.’

What fascinates me is what this mistake reveals about human decision-making. A higher intelligence might notice immediately that the sign is in the wrong place; we don’t. When presented with inadequate or untimely information we are oblivious to its limitations; instead we make do with whatever inadequate information is available and carry on.

One of the world’s worst signs, as seen on Google Street View
One of the world’s worst signs, as seen on Google Street View


Major decisions in life — where to buy a house, for instance — are made by rapidly comparing at most two or three options. We are blind to the narrowness of our search and unconscious of any pertinent information we lack. Daniel Kahneman calls this phenomenon WYSIATI — ‘What You See Is All There Is.’

So for decades, when faced with a patient with tonsillitis, GPs assumed they had a simple choice: either a) prescribe antibiotics or b) don’t. Only recently did anyone realise there is another option: you can issue a post-dated prescription for antibiotics. ‘If you aren’t feeling better by Friday, take this to the chemist.’ Almost all patients given an immediate prescription will take antibiotics, and often unnecessarily; this proportion drops to around 35 per cent in the case of a deferred prescription. I’m not saying the third option is perfect — but it helps to know it exists. For decades it seems nobody did.

Recently there can be no better example of WYSIATI in action than the reams of journalistic guff written about the Clarkson incident — where at most six people on earth really know what happened. Deborah Orr even wrote an article in the Guardian which began with the words ‘Details of the fracas are as yet sketchy…’ and ended with ‘Clarkson should do the decent thing, and resign.’

However, the BBC — which presumably does know what happened — has also failed in its decision-making. Faced with an incident of this kind, there is only one decision you can make: a quick one. You can encourage the two people to make up over a pint, or you can fire someone; either decision is perfectly fine so long as you make it fast. Often the likelihood that people will respect a decision is proportional to the speed at which you make it.

Got something to add? Join the discussion and comment below.

Rory Sutherland is vice-chairman of Ogilvy Group UK.

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Show comments
  • kentgeordie

    You think there are many problems you can solve by quickly firing someone??? Have you ever heard of employment tribunals?

    • rorysutherland

      The point is that we assume that decisions taken quickly are clear cut decisions, while those taken slowly are political and ambiguous.

      • CouchSlob

        One might as easily say that decisons taken quickly are rash, and those taken wth consideration are more likely to be correct.

        • rorysutherland

          A decision is often not really “correct” either way. What matters more is that people automatically understand and accept it. I was told this from a general in the army.

          • CouchSlob

            That may be true on the battlefield. In the workplace however, there are procedures for terminating someone’s employment. It’s obviously more important to get it right than to blindly rush to a decision just for appearance’s sake.

  • Jackthesmilingblack

    Once you make a directional error, you are subconsciously programmed to make the same error next time.

  • Andrew Rose

    “So I logged on to Google Street View and retraced the stretch of the M20
    leading up to the junction. That’s when I found the image below.”

    So did I, which is where I found the three signs that come before it. There’s a sign a mile back, a sign half a mile back and an overhead sign just like the one in the picture 1/3 of a mile back. The author clearly needs a sat-nav!

    • rorysutherland

      Yes – I didn’t have space to describe the other failings. None of these earlier signs has any indication of distance (2 miles? 1 mile? 1/2 mile?). There are no three-two-one hundred-yard bars to remind you you are approaching the point of no return. None of the signs mentions destinations by which you can easily navigate (a “primary route destination” such as Brighton, Gatwick, etc). And when you see these signs, the final gantry sign is already visible, and you not unreasonably assume that this final sign will give you enough time to act on it.

      I didn’t make the mistake when I first made the journey and had my satnav turned on. It was only when I thought I was sufficiently familiar with the route that I started missing the turning.

      I have done a show of hands with audiences in London and about 5-6% of people seem to have made this mistake.

      • Andrew Rose

        Look again. The overhead one before the one in your picture says 1/3 mile. The one at the side of the road before that one says 1/2 mile. The one before that I can’t tell you as there’s a lorry in the way of the Google camera, but I’d put money on it saying 1 mile!

  • Dan Grover

    I think the M25 has another problem in the form of the North/South or East/West thing. It’s not a straight road, it’s a giant circle. As such, compass point directions have a limited usefulness. If someone’s planning a journey, they’ll almost always know if they’re going clockwise or counter-clockwise, but not neccessarily if they are – at that particular part of the journey – going N,E,S or W because your orientation is constantly but slowly changing. I’d much rather it were labelled CW or CCW as a result.

    • jatrius

      I think anti-clockwise would be a more familiar term to the non-Americans but , yes, it makes a great deal of sense. Perhaps a visual circular arrow such as you see on screwcap bottle tops, rather than more letters..

      • rorysutherland

        This is fair. The other failing is that the three signs leading up to the junction do not mention what is called a “primary route destination” – something like Gatwick, Stansted, Brighton, Cambridge, etc…..

        I don’t think even everyone who lives in Swanley knows whether it is north or south of the M20 – most people know Swanley as the name of the interchange itself (made more famous as the location of Kenneth Noye’s “road rage” stabbing).

  • Nick

    Driving around Hyde Park Corner in London scares me.

    Whenever I drive around the giant roundabout there,people in other vehicles scream at me.I see them waving their fists and other things at me.They froth at the mouth and I can see their teeth.

    It’s like all the other drivers have got rabies and are out to get me.

    What am I doing wrong?

    • MiddlelandExile

      Er.. just a guess, but try concentrating on good lane discipline rather than other drivers’ fists and mouths?

      • Nick

        I’m thinking of buying a Humvee.

        • MiddlelandExile

          That should work…

          • Nick

            Well a Humvee is a bit more intimidating than my black Kia Picanto.

  • Luke Cresswell

    So long as you know you need to join the M25 (in either direction) the previous 3 signs make it clear which lane you need to be in. This is reinforced by a change in lane markings that signify that lane one separates from the current carriageway.
    I imagine the chevrons are to deter people from changing dangerously at the last minute, and that the final sign is an indicator making people oblivious to the previous signs aware that they have missed their junction.
    Too many people cut across at the last minute at far too many motorway junctions (often to drive past as much traffic as possible in the lane they need!
    I’d want these chevrons (or more ideally a separating barrier) at as many junctions as possible to reduce or eliminate the risk from these dangerous practices.

  • kentgeordie

    This is an interesting junction is that you have two opportunities to join the M26, both signed. Don’t blame the junction or the sign if you are not paying attention.

    • rorysutherland

      The turn off for the M26 is a good few miles back. Turning off for the M26 and you are stuck on the longest section of UK motorway without an exit – 18 miles to Godstone – as you can’t turn off at Sevenoaks, for reasons that have never been adequately explained..

  • With reference to Clarkson, it was in the economic interests of the BBC to resolve the issue so the revenue stream would be preserved; even at the risk of a lawsuit from the aggrieved party. So why did they act otherwise? Is it that they are political wankers and care more about a temporary tempest in a teapot than serving their audience with great programming? Or are they just wankers? Clarkson might be a total douchebag, but he is an entertaining one. So I want him reinstated.

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