Much is said about the importance of the recoverability of errors online, and how frustrating it is for the user if they are not able to simply backtrack a step or two without losing all their data. However little is done on too many sites to make an error recovery as painfree as possible for the user.
Over the phone
Some things you just take for granted until it goes wrong. e.g. when you are giving someone your telephone number over the phone, you say a part of the number wait for them to say it back to you, then continue with the rest of the number. Each time validating that the other person has collected the right information.
Its a simple learnt action that saves all heaps of bother with miscommunication.
In a restaurant
Image © eblaser
The same goes for when you are at a restaurant and you place your order, then the waiter reads it back to you from their pad before leaving your table. A simple common process. However, what happens when the waiter doesn’t read your order back to you? You’ll end up receiving the wrong food as I did once.