Gillies having been involved in the IT industrie for some time, I have a good idea how it works.
Let's just say, people need work, and admins need to be seen to be "doing" something, so sites that work perfectly well and could easily incorporate new requirements, will be redesigned. It's called "progress"!

When the Supertab site was going to be redesigned a few years back, I talked to one of the blokes involved before it was going ahead, he said there was nothing really dramatic needed doing, but it was "due" for an upgrade.
He was happy of course and I can't blame him either.

I wish some of these teams of designers would be paid just to sit around, and only work when absolutely necessary, same as public "servants" and politicians, if we must have them, then at least let them do no harm!
Fat chance of that though.

Cheers