In the United States, Sesame Street is a popular television program for children, much like Manchester United football is in the UK. Its Web site is sesamestreet.org. Now, suppose you were visiting the site looking for some simple, puppet-based best practices videos that you hope against type that your project managers could understand. Say, “Elmo Learns About Gathering Requirements.”
You click the Videos link at the top and then you can click the GO link beside the Search Videos edit box.
Oops, it doesn’t validate to make sure the user has entered something besides the default label value Search videos. The search results display for videos containing or somehow relating to Search videos:

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One more video. Click Next.

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These results don’t show what I’m looking for, so I’ll go Back.
Now, what’s wrong with this picture?

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Notice that the results are in a different order. Not only on this page, but the result which had been number 10 on the second page now displays on the first page.
This is really, really crazy when you have 10 pages of results, such as the search for “Abby Teaches Zoe Not To Mark Defects As Closed When Zoe Wants To Improve Defect Counts For Client Milestone Meetings.” In this case, if you go backwards, you will see a completely different set of results as though it had conducted a completely new search.
You know, result pagination and not re-sorting results without user input are pretty basic functions. Unfortunately, so many times organizations and development staffs take basic things for granted and don’t test them. After all, they’re only re-implementing the wheel, not re-inventing it. So they don’t bother checking to see if they inflated the tire, or as you call it in the UK, the boot bonnet tyre.