Track all credit notes issued.
The number of credit notes that your business issues directly measures how well or how badly your business processes are working. Wrong goods, wrong prices, wrong discounts or whatever, the process of correcting these mistakes certainly costs you a lot of money. Monitor credits, categorize them, analyze them and then focus on the problem areas in your business that causes them. Targeting improvements in these specific problem areas will save you time and money as well as dramatically improving customer service