I think this has been discussed before, but there is an element of truth in that quote. It's not uncommon to discover what the client needs/wants and what they ask for are two different things. This discrepancy or gap is usually caused by external factors. Who's to say that after a visit to Best Buy or what ever chain or some TV ad that the client has got a particular technology in mind that, but in the long term it will not suite their needs.

The only way you can truely understand what a client needs is by talking to them and asking the appropriate questions during the intervue process to determine what they need, so that you can seperate needs from wants. But the real truth is everything a designer or custom integrator does does not take care of needs (i.e. basic) , we can only take care of the wants part of their life. However, at the end of the process, hopefully I can determine what client wants and have convinced the client that they really need it.

Just my .02

Cheers