On the selenium-user mail list, it was hypothesized that candidates rate themselves well in respect of their skills match to the job in question. It was said “No One Gives Themselves Bad Ratings”.

It turns out that this is not universally true: Real experts, when questioned, often rate their own skills as lower than they should.

The Dunning-Kruger effect (DKE)

This epiphany is one of a few that comes out the research that Dunning and Kruger have done to explore long-believed tendencies within society. The definitive write-up is on Wikipedia, though that’s not very prose-full.

Easier reads are available: New York Times article from a year ago and a Psychology today on the same timescale. Here is one from the turn of the millennium that I particularly like on the San Francisco Chronicle.

The one-line take away:

  • The skills to recognize incompetence in others are the same as the skills to recognize incompetence in self.

The slightly longer version:

  • Candidates who are experts, typically rate themselves lower than they really are, and incompetent ones rate themselves higher. The competent ones only realize the injustice of their position in the rankings, when they are confronted with the self-determined scores of those that they already knew were less competent.

In summary, be wary of rejecting candidates who self-rate to scores lower than a threshold you have set. Always do some independent verification.

Steve Jobs’ view on A, B and C players

Steve Jobs said: “A players hire A players, B players hire C players”. This has been written about a few times, but perhaps Guy Kawasaki is the most lauded witness to it, and can give the best explanation. I like to remember that B players also (typically) reject A players. The worst of the resulting teams will self-repairing back to B/C level.

^ That from a previous blog entry. A’s, B’s and C’s in particular suggests that incompetents should be removed from hiring or you will end up lowering the bar. Steve Jobs may have been one of many that was preempting the later findings of Dunning and Kruger.

Incidentally, I have to thank Agile industry legends Chris Matts and Andy Pols for first putting me on to this stuff in 2002.


Here’s a link to the original 1999 Dunning-Kruger paper

Ars Technica revisited why incompetents think they’re awesome (May 25th, 2012)

Quora has question on What is an A Player (October 2012). It has a Steve Jobs quote from the Walter Isaacson biography, on A players generally. It also refers to Jack Walsh as the coiner of A’s B’s and C’s in this context, though the that book was first published in 2001.

Checking with Guy Kawasaki (by email - Nov 3rd, 2014), he says “I am pretty sure that Steve was saying this around 1984.” Guy indeed went on to mention the same in What I Learned From Steve Jobs (2016).

There’s also a Quora question on Is it true that A players hire B players, and B players hire C players? (October 2012) that is worth a read, even if it gets the Jobs quote wrong .

Christie Nicholson on the smartplanet.com web site interviews David Dunning in an article that speaks to recruitment (amongst other things) - April 4th, 2014.

Psychology Today deleted their article some time in late October 2014. I’m not sure why. The link for that now points to the page in the Internet Archives’s Wayback Machine.

David Dunning himself, in Pacific Standard Magazine, does meta-analysis of more recent studies, and contemporary media analogues (October 27, 2014).

And again doing an “ask me anything” on Reddit in late 2014 - Science AMA Series: I’m David Dunning, a social psychologist whose research focuses on accuracy and illusion in self-judgment (you may have heard of the Dunning-Kruger effect). How good are we at “knowing thyself”? AMA!


August 9th, 2011