Slips and Mistakes: Two Types of Errors
It can be helpful to categorize errors into slips and mistakes. Don Norman has written extensively about slips and mistakes in Chapter 5 of The Design of Everyday Things.
Slips are the classic unintended action a user makes while trying to do something on an interface even though the goal is correct (e.g., a typo) .When the goal is wrong it's a mistake, even if that goal was accomplished.