Except experience shows they aren't. Experience shows that when humans are just pressing "ok" 99% of the time they'll press it 100% of the time and completely miss the other cases.
This is a matter of appropriate training and regular refreshing over time.
The best known example is the Japanese method of "Pointing and Calling/Naming" in their Train safety protocols but has been adapted to other industries too - https://en.wikipedia.org/wiki/Pointing_and_calling
These fall under "Behaviour Based Safety" (BBS) training methodologies and use techniques like "Check-backs", "Call-outs", "STAR" etc.
This is a matter of appropriate training and regular refreshing over time.
The best known example is the Japanese method of "Pointing and Calling/Naming" in their Train safety protocols but has been adapted to other industries too - https://en.wikipedia.org/wiki/Pointing_and_calling
These fall under "Behaviour Based Safety" (BBS) training methodologies and use techniques like "Check-backs", "Call-outs", "STAR" etc.