On Necessity

When working with users, I am frequently reminded of this conversation in David O. Russell's movie Three Kings:

This is a companion discussion topic for the original blog entry at: http://www.codinghorror.com/blog/2005/03/on-necessity.html

I assume you’ve also read Malcolm’s Gladwell’s “Blink” – also about decision making, although his emphasis (including among people whose decisions are super critical) is in how fast decisions are made.

Maybe that has something to do with the format of a lot of multi-day competition, in which the people who score better on the first day go last on the second. Even in events where that is not the case, an experienced judge may well subconciously weight the latter performers scores higher out of simple habit.

The “going last results in a better outcome” phenomenon is something I’ve read about a few times … ah, here it is:

In fact, the idea for the research emerged when Bruine De Bruin was looking for an apartment herself. It would be nice if we could see all the options available when we are trying to make a decision, she says, but “in the real world it doesn’t always work that way. You can’t see all the options at the same time.” Even while looking for an apartment, she says, she tended to exaggerate the importance of the good things in the apartments she viewed last as opposed to those she had seen earlier.

You can also see this in action on Penn Teller’s Bullshit DVD, season 1, disc 2. It’s the episode where they test “pheremones” using twins.


It’s really shocking to see, because it is so… repeatable. No matter what they varied, across dozens of people, the second twin was always picked. If I hadn’t seen that DVD prior to reading that article, I’d be skeptical too.