Why Two Signatures Guard the Club Treasury
The Robotics Club has a bank account with money from fundraisers and dues. To take any of it out, a check needs two signatures: one from the treasurer and one from the adviser. It might sound like a lot of fuss for a few hundred dollars, but the rule has good reasons behind it.
First, it protects against mistakes. Everyone makes errors, such as writing the wrong amount or paying a bill twice. A second person looking over the check has a chance to catch the problem before the money is gone.
Second, it protects against temptation. When one person alone controls the money, it is hard for others to be sure it is used properly. With two signers, no single person can spend the money in secret. This protects the club, and it also protects the treasurer, who can always show that someone else approved each payment.
Governments use the same idea on a much bigger scale. In a city, the person who approves a payment is often different from the person who writes the check, and a third person may review the records later. Splitting up the steps is called a check and balance, because each person checks the work of the others.
The system works only if people take it seriously. A signature is a promise that you looked carefully, not a quick scribble.