We humans are naturally lazy. If given the choice of mowing the lawn or laying down and watch TV, what is the only choice? Point made.
Now, when it comes to our computers, we are just as lazy. Who wants to remember some log-on password with numbers, letters, and special characters? Why not just use your birth date and name. Sure no one will crack that spy master code!
Face slap...wake up and read this... Worst Passwords