Adam C. Engst, in his overview of Keyboard Maestro 6:

In fact, many of my macros are utterly simple and obvious — I could type “cheers… -Adam” at the end of every email message I send, or I could press Control-period. Just because I’m saving only a few seconds doesn’t mean that it’s not worthwhile, when added up over tens of thousands of messages. Similarly, much as I love LaunchBar and use it heavily for many things, because I set F1 to open BBEdit via Keyboard Maestro, switching to BBEdit via F1 is a third of the work of LaunchBar’s Command-Space, B, Return. Those infinitesimal bits of time are like the energy drain from glowing lights on otherwise inactive electronics — meaningless in the individual instance, but vast in their overall impact.

According to Keyboard Maestro, I have saved 420 hours since I started using it 635 days ago.