Safety concern
There have been numerous accidents worldwide that were the result of simple human errors in data calculation or entry.
Data errors—such as the wrong figure being used as well as data being entered incorrectly, not being updated, or being excluded—happen for many different reasons.
The consequences of these sort of errors can range from aborted take-offs through to collisions with the ground. Errors can occur irrespective of pilot experience, operator, aircraft type, location and take-off performance calculation method.