Customers often use the cart as a storage and comparison tool. As such, they tend to add multiple variants of the same item (four comparable cameras for instance). Due to the fact that online shopping often takes place over multiple sessions, shoppers tend to lose track of all the items in their carts. This might lead to sticker shock when they eventually try to check out.
While removing items from the cart is always an option, it’s not ideal, especially if the customer is just about to check out. The more unwanted items a customer has in their cart, the longer clearing them out is going to take. The longer people spend pondering a purchase, the more likely they are to change their minds. Even if they don’t reconsider the purchase, it still makes for a subpar user experience.
Showing customers a count of everything they have in their carts gives them an idea of how “full” it is. Whenever they see that the cart is getting crowded, they can always go and do some light housekeeping by purging the cart of unwanted items. This practice should go hand in hand with keeping your cart persistent (see BP #106) and having the cart icon as part of your header.
Show the cart total
You can also keep a running total of all the items in the cart. This limits the sticker shock as a customer can see the total before accessing the cart page. It also let’s them know when they’re exceeding their budgets and might prompt them to check out sooner than they otherwise would.