Why must I enter a PIN for purchases of $15 and more?

As a precaution, we have set to $15 the limit of purchases that do not require confirmation via a PIN. We have deemed it to be a fair maximum amount over which instances of fraud or theft are easily traceable. In that sense, we find that purchases of $15 or more require consumers to be more mindful, and that is why it is important for users to enter their PIN to confirm these transactions.