I remember, years ago, working on a mobile web service which had a URl bar - so users could tap in bbc.co.uk on their T9 keypads - and a separate search bar. I thought that was pretty nifty. But it turns out, users tried searching for URls and they tried going to "http:// When is the Next Bus?". Bloody users!!

Users find input bars confusing. A good example of this is Amazon's search bar. It faithfully records what everyone is searching for and uses that big data to suggest to other users what they might be interested in. Which leads to some "interesting" results.

Here's what happens if you start searching for https://

(And, yes, I used an incognito browser so it wouldn't be polluted with my own demented midnight searches for corrugated iron flavoured pogo sticks.)

There are a few lessons to take away from this.

• Users don't really understand interfaces
• Computers don't really understand users
• Big Data assumes that users are behaving in semi-rational manner