As a child I was confused by the word boondoggle and how it was used - from my parents' wide vocabulary I knew that when a thing was a boon it was a good and helpful thing; and, doggle was obviously a cute way of saying dog; therefore given the way the English language works a boondoggle was obviously a cute and helpful dog.
Umm ...
No ...
I lost the war the very second I applied logic to the English language ...
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"There are a thousand things that can happen when you go light a rocket engine, and only one of them is good."
Tom Mueller of SpaceX, in Air and Space, Jan. 2011