I've always been so careful. I always check addresses before sending: the first four, the last four, a random slice from the middle. Confirm on screen, confirm on ledger, do it again. Run a simulation, check the outputs.

Never made a mistake.
But last month I fat fingered my bank account number for my pet insurance coverage and today they directed my $5000 reimbursement to that wrong account.
And they say it posted successfully.
ggs. Pour one out for your boy, for today I join the ranks of the victims.