While the term "Three-Click Rule" now refers to "The three-click rule or three click rule is an unofficial web design rule concerning the design of website navigation. It suggests that a user of a website should be able to find any information with no more than three mouse clicks." (source), I had originally defined it differently, back around 1997.
In 1997 I worked for an Orthodontic & Oral Surgery software reseller called Ortho-Vision Technologies, Inc.. I initially worked as tech support for the company's software products and later I created their advertising and marketing collateral.
During this time it became apparent that a certain cosmic rule applied to computer-based clicking errors. Thus, I came up with the "Three-click rule".
For every click in error, at least three clicks are required to undo the error.
While it is evident that this doesn't apply to basic "oops" moments in Photoshop or the like, but rather it applies to those moments where stupidity and inaccuracy combine for you to select the wrong website, open the wrong application etc. I find my three-click rule still applies, even after a decade of clicking in error.