[user104658]

Originally Posted by Blurryface

The show would've been the same if Davina Presented it. Emma's not production manager, she's host.

Well... the host DOES also make a difference, to be fair. Say what you will about The X Factor over the years but IMO one thing that is undeniable is that Caroline Flack and Olly Murs were absolutely dire as hosts, and the people behind the show knew it too, hence re-hiring Dermot who love him or loathe him is simply a much more competent host.