EXPECTATION BIAS: the inherent tendency to see it as it "should be" rather than how it is.

In 2006 NASA conducted a major study that focused on checklist error.
Expectation bias--Calling 20, when they were really at 8--or calling set when they in fact were not was a common event.

In time, the verbal response becomes disconnected from the action.
When I hear "Landing Check" I still can remember "Landing gear down, flaps 45 degrees, set and indicating, flight attendant advised, landing check complete" and I have not been in that plane for 5 years.

This bias is increased under stress, fatigue, workload, or distraction.
In terms of the ability to multi-task, the latest research shows it is "routine but risky."