Share of Wallet
There are several ways to measure the satisfaction of your customers. You can of course measure the sales results and development over time, compared to your competitors or the market. This will tell you if the share of wallet with your customer base is growing or declining.
Share of wallet is an important metric to measure the satisfaction of the customer. In the end, loyalty is about earning more money from the same customers. However, the method tells little about why customers spend more (or less). For this other methods to measure customer satisfaction are more suited.
Another way is to simply ask your customers whether they are satisfied and what you can do to improve your service. This can be done at every point of contact with the customer. During a call, a visit to the website, in emails send. You can just ask customers about the reasons to abandon their basket on your website. It is also possible to ask for customer feedback or reviews after the purchase or delivery.