Stall.
Most of us in-game stall out 10-15 times a day and think nothing of it...we either use it as a tactic or have learned how to easily recover from it.
Not so in the B2.
There is even an on-board computer that will not allow a pilot to intentionally stall the aircraft.
However, wind conditions, engine failure, and a few other conditions could bring about that 1 in 500,000 situation where the aircraft stalls. Hit the button and bail.
ROX