Why would you monitor your sales? Do know that they indeed happened to put it in short. Sales are not just about making accounting entries, but also ensuring that your customers are getting what they ordered. If you think about it, in a case where the sale hasn’t in fact taken place (that is the customer didn’t get anything) you’re not getting paid either (and you could be asked to pay back any prepayments made for the purchase by the customer if that’s the case). 

You might say that it’s only an issue if you’re having different people dealing with orders and shipments, but I would say that it’s not so. Yes, if there’s just one person dealing with both processes, mistakes are lot more rare to take place, however, they can take place. And not just mistakes, but possibly also a fraudulent activity by this one person – for an example he or she could agree with your customer some form of transaction where the customer orders one amount, actual delivery is considerably bigger and yet the receivable and sale again is for this smaller amount. Trust me, when you give people the opportunity, they can be very creative.

So how can one avoid such situations? There can of course be other measures, but one that works is comparing shipments against customer orders just before the delivery is about to be made to the customer. That is, you’re ensuring that what goes out from your company premises is in fact what the customer ordered and what’s being invoiced for.