Authorize.net took a dive in this web designer's view.
It just goes to show how a company can ruin 9 years of good service in two weeks. Two lessons:
1) The fact that someone wants to stop a current relationship doesn't mean they stop being an important customer. Treat them as such.
2) Your customers expect perfection. Aim to deliver.
Fortunately these days most companies don't differentiate themselves in customer service, so you don't have to work to hard to match them.
Of course you can never please everyone, and having an unhealthy need to please can be very distracting and unproductive. But here a great reference (and you have to think there are many more than one) was lost because of a drop in customer service. It matters, but companies don't know how to sell it, so they often skimp on it.
My worst experience was with a company that sold, for money, it support services (called Maintenance). When you called support you got someone with an Indian accent who didn't know, and who's manager didn't know, the meaning of the work "migrate." And this was a service they sold over and above the price of the product. The even solicited the business after we had let the maintenance laps. They won't get my recommendation again, even if their product is technically superior to the competition.