You made a excellant point!.You actually nailed the difference between checking and testing.

Most sites payment processes goes through a third party and most of the time you’ll find that your carefully selected shopping cart is cleared if you change your mind once it hits that 3rd party service.

Michael replies: Yes, sometimes it is cleared—and sometimes it isn’t, too. I went through a similar transaction yesterday, somewhat different from my wife’s experience. For me, there was a default limit on the amount of money I could pay through my bank, so my first attempt to pay didn’t complete successfully. I contacted my bank and raised the default. Then I went through the payment process again. Just in time, I noticed that the shopping cart hadn’t been cleared, and my order and my payment were doubled. If I hadn’t noticed this, I can’t imagine the grief I might have gone through—having to find the department to issue a refund, a non-trivial delay in processing the refund and crediting the account, a possible overdraft for that account…

So, another item to add to the list:

What happens if the customer makes an excessive or extra payment? How will that get resolved?

Most 3rd party API’s don’t cater for this either, hence why I’ve always thought it is essential that testers get involved in the early API design process, so we can spot the “what if” scenarios like this.

Sadly we don’t play a part in the design of the 3rd party services we choose.

True… but we might play a part in the choice of those third-party services. Are managers aware of the help that we can offer there?

Very nice post, thanks for sharing Michael.

And thank you for your comment.

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