Lets consider this - Foreseeability - need to lock door, pay $1,800.00 to do so. Use pin code, because of convenience - important people cant remember the code, and less important people have shared it with everyone. Now, premise liability, using a credential that is easily shared, easily guessed or EMBOSSING A COPPER PLATE AND MOUNTING on the WAL PeRmAnEnTlY!! with the THE CODE 9,8,7,6* on the wall. Threat exposure is 5,4,3,2,1