This is what comes to my mind from my personal experience. Your customer uses excel spreadsheets to coordinate work. They ask you to move what they are doing in excel into custom software that can be shared with other users. If your not careful as a developer you end up re-inventing excel.

What is more important is to understand what the customer/user actually needs and solve that problem. Often times customers do not understand how software could make their life better.

In other words the customer might be asking for a faster pencil (the current tool) but what they really need is an email system.