With TOS it’s important to use the (+) (-) to increase decrease values. I’ve manually entered numbers without hitting the RETURN key. The system doesn’t recognize the new value without hitting RETURN.
Anyone who's been an active automated trader for far less has made mistakes.Please. Anyone who's been an active manual trader for 20 years has made mistakes.

I once hit my own stock bid. I entered an order to buy 500 at X. I wanted to enter another order to buy another 500 at the same price. I was using Redi at the time. I found it faster to click on the bid to create the order then switch to buy, as clicking on the bid creates a sell order. I forgot to flip it to buy.
oops.

Last year, I sold an option spread on the CME for a debit of 3.90 when I wanted to enter. A Credit of 3.90. I learned that the CME charges $1000 to investigate an obvious error. As the trade was a 1 lot, and he loss was less than $1000, and it did not meet their criteria for obvious error, I had to eat the loss. It happens.
those who cannot trade or admit failure become brokers.
Hah. Nice assumption. I made a good living for 25 years. Are you even 25 years old?