I knew most of the people reading this would assume I'm speaking dev. Really I would repeat this 10 times a day on the phone to my automotive customers that had over 300k miles on there vehicles and never replaced a part besides an oil change wanting me to make more power in firmware but their clapped out pile couldn't do it because it lost 3/4 of its compression or was leaking oil internally so bad it was a miracle it was running at all.

Customer: "It was running perfectly yesterday then I put your firmware on it and it runs like shit"

"Running perfectly yesterday" = "misfires, smokes when its cold, doens't want to start, has no power"

But it was always my fault XD