New is New's idea is just to trash the well-recognisable wikipedia W, and replace it with a new one, with no good reason.

And trash the icons for the various Wikimedia projects.

people who get paid for coming up with new icons and logo's are going to create new logos and icons.. it's what they do.

Is there every a "reason" to create new logo's or icons? Other than someone feels a new for a new or fresh look...

Well, sometimes companies feel their current logo is too out of date and they want to change it.

Or sometimes companies rebrand completely, sometimes because of a shift of focus. (A company I know about shifted from discrete software to B2B software and changed its branding in the process)

A legitimate reason is when a company or organisation changes significantly. Wikipedia changes remarkably over time, but does it incrementally. Logo change is neither sensible or required.