These true anecdotes about sum it up::

7. Client can’t articulate a single desired user goal. He also can’t articulate a business strategy, an online strategy, a reason for the site’s existence, or a goal or metric for improving the website. In spite of all that, client has designed his own heavily detailed wireframes.

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10. On the eve of delivery, the previously uninvolved “vision guy” sends drawings of his idea of what the web layout should look like. These drawings have nothing to do with the user research you conducted, nor with the approved recommendations, nor with the approved wireframes, nor with the approved final design, nor with the approved final additional page layouts, nor with the approved HTML templates that you are now integrating into the CMS.

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18. As approved, stripped-down “social networking web application” site is about to ship, a previously uninvolved marketing guy starts telling you, your client, and your client’s boss that the minimalist look “doesn’t knock me out.” A discussion of what the site’s 18-year-old users want, backed by research, does not dent the determination of the 52-year-old marketing guy to demand a rethink of the approved design to be more appealing to his aesthetic sensibility.