Here is a fictitious story of a business client that orders software for a mobile phone to an embedded developer.
Take such a trivial feature of a mobile phone as a the possibility to store last calls. What do you know about it besides that it allows to view last incoming and outgoing calls? This is the level of knowledge that a typical client has and he will express it as a requirement the same way:
— I want that my mobile phone software to store last incoming and outgoing calls.