Use "the human factor" in a sentence

1. Our main competitive advantage lies in the human factor.

2. The Air India bombing is proof of the importance of the human factor.

3. ‘He invented a Cryptograph or secret despatch writer, which is supposed to be indecipherable.’ ‘The new machine, called a Cryptograph, in receiving the message as originally written by the sender and enciphering it mechanically, eliminates the human factor of the code clerk.’

4. ‘He invented a Cryptograph or secret despatch writer, which is supposed to be indecipherable.’ ‘The new machine, called a Cryptograph, in receiving the message as originally written by the sender and enciphering it mechanically, eliminates the human factor of the code clerk.’