What is your most expensive mistake?

When I was rather young I answered my parents company phone. The caller asked for my mom by her first name. I explained he meant Mrs. “....” because my parents were old school and taught me not to address adults by their first names. Clearly I got the wires crossed on the call.

So caller got rude I got rude and caller hung up.

Turns out caller was parents #1 client with no patience for such shenanigans. He kicked our company to the curb almost immediately after citing this incident and it cost us a net of 20K a year (1987) which was about half of my parents entire annual net.

Surprisingly I was never abused following the pay cut I gave my parents.

/r/AskReddit Thread