The only time I ever switch hotels on a vacation is because:
1) The original hotel is absolutely unacceptable upon checkin
2) We are going to multiple cities on the same trip (did that last summer when we toured baseball stadiums.
I know that there are folks out there that love to experience multiple resorts while at WDW. IMHO, the time spent changing resorts (repacking, checking out, being 'homeless' until your new room is ready, checking in, unpacking) is time better spent relaxing by the pool or enjoying the parks. I simply don't want to spend one minute more on these chores than absolutely necessary when I'm there.
Just my personal preference.