Customers are doing you a favor whenever they point out problem - listening and acting on their advice can pay off.

I received an email from a visitor to my site at http://www.sitebank.com, telling me I had an error on the page that prevented his ordering one of the products there.

I immediately checked the page, clicked the order button, and found that things worked as intended.

I thanked the emailer, and assured him that the page did indeed work.

Two weeks later I'm adding new products to the site, updating the index page where the customer clicks to order the product.

Guess what I found - a coding error that preventing orders from being placed. Exactly as the emailer had told me.

So how did I miss it?

When I tested the page, I tested from the point of view of the person who designed the page. I used the 'logical' order button.

But there were other ways to reach the order form, and my coding error created a road block on those other ways.

Moral of the story - listen twice as hard when a customer points out a problem. In most cases, it is a real problem, at least to the customer, and even if you are sure the problem doesn't exist, your customer is probably right. There is a problem of some sort, and it is worth fixing.

Unless of course, you can afford to throw away customers and orders.