Quoted from Coindork:
Out of curiosity, what's the point of installing a play meeter when the machine counts coin drops in the audits?
Was there an issue where operators had multiple people that had keys to the games and would delete play counts to steel quarters?
In some localities hard wired meters are required by law. In areas where they are not required, operators may choose to install meters on their own. Here are some reasons for doing so:
Ram chips on cpu board corrupted.
Batteries for ram chips died or run down too low.
CPU board had to be replaced for some reason.
Location doesn't have power turned on to outlets machines are plugged into yet when operator's routemen show up to collect. Sometimes outlets are on a timer.
Cheating operator's employee zeroing out audits on machine and skimming money.
A hard wired total play meter is like an odometer in a car. It gives a person an idea of how many true "miles" are on a particular pinball machine over it's entire life regardless if the batteries died or the audits got reset. Stern and other pinball machine manufacturers still provide optional coin meter hookups in the machine itself or provide a meter kit you can install yourself.