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Inadvertent errors are when the operators become aware of the error only after it is too late.
The operators might press a wrong key or button.
The operators jumped too fast to a conclusion and to make the next step. Only after the execution, they realize that they made a mistake.
Accessibility means that the operator's command is promptly accepted, without asking the operators to verify that they activated the command with full awareness of the implications. Therefore, accessibility facilitates the command activation, but are prone to inadvertent errors.
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