At least the FF series always does new things in each of its installments, and so far have succeeded every time. The only thing that anyone could really have a point against SE is the use of the FF name. SE puts FF on far too many of their titles and creates too many spin-offs. But other than that, the games themselves are always new and refreshing one way or another and there is always a different way to enjoy each new FF/FF spin-off with different game play/settings/stories/characters. Some could argue the "if it ain't broke, don't fix it" statement; how about "if it's old, try something new and improve it because it feels like we're reliving the past".
This will only take a moment of your time. *steals your watch*