With an Airbus, human factor is taken care of in a way. Flight envelope keeps the plane from stalling or going into a nose dive or excessively banking. Plus, the MCDU has error checking.
If you put in the wrong numbers into the system, it can choose to reject them for being mathmatically incorrect, either requesting a new number, or just not automating that thing.
In contrast, in a Boeing, human error is allowed to happen, and in all but the 777 and 787, this means that even the computer system doesn't even check for errors.http://avherald.com/h?article=4ac18a5b
This was an incident with a Boeing 737-800 during takeoff. The pilots were using the Engine Derate system (basically the same as Airbus Flex Temp), and inputted the wrong numbers into the FMC. This lead to takeoff being messed up and V1 and V2 occuring at the wrong times. Following investigation by AAIB, it was determined that had there been an engine failure/fire after the late V1 point, the aircraft would have crashed.