Good clients often say they want to simplify their websites by "removing the clutter". This is an admirable ambition, but it's important to be clear what we mean by "clutter".
Usability expert Jared Spool shares an example of a company intranet home page regarded by staff as being "cluttered", despite the fact that from a visual design standpoint it was rather neatly laid out with plenty of white space, readable fonts etc.
What the users were objecting to was the fact that the content was largely irrelevant to them. The marketing department had dumped a load of links it wanted people to follow, which were making it harder for people to find what they really needed.
The redesigned home page actually contained more content, not less, but it was no longer viewed as "cluttered" because it was all now genuinely useful.
Simplicity is not about "clean", sparse designs (although that may often be the result). It's about including what's really necessary and excluding what's not.