There are some advantages about being in at the start of the Internet and building applications based on videotex technology. Along the way I had the pleasure of meeting up with Dr Peter Cochrane, who from 1994-1999 was Head of Research for British Telecom (which developed the videotext service) and went on to be Chief Technologist for BT prior to his retirement in 2000. Peter was, and indeed still is, a charismatic public speaker and in the late 1990’s was a very frequent speaker at conferences. I still remember having dinner with him after a conference I had organised at which he ranged widely and with tremendous insight over every branch of technology.

So what is the connection between Peter and the ‘three clicks rule’? Today I was alerted via Twitter to a blog post about the fact that the three clicks rule was not helpful in designing web navigation. This came as no surprise to me because the three clicks rule was proposed by Peter in around 1998/1999 and had nothing whatsoever to do with navigation structure optimisation. Peter was a telecoms engineer and his concern was over bandwidth latency as the use of the Internet increased but was still largely running over copper and not optical fibre. It was typically taking 15-20 seconds for a page to load in response to a click and so three clicks might take a minute to complete. If you think this is unbelievable read this paper from 2004 on tolerable waiting times for web users!

His concern was that unless there was a significant network capacity upgrade world wide the delay for a user even needing as few as three clicks would be such that they would give up the task, and that as a result the Web might never fulfil its potential.  He wrote this around 1998

“Who would like a three click, one second, no handbook world? Drill down to anything you want in three clicks of a mouse, and it appears on your screen in under a second! No need to read a handbook, no training – just the application of intuition – an obvious and easy to use interface for everyone. The only prospect of realising this dream relies on ‘end-to-end’ optical fibre and significant improvements in network and computer protocols, interfaces and software.”

This is just to put the origin of the three clicks rule on the current record and hopefully to stop people wasting their time trying to prove or disprove a half-remembered proposition.

Martin White