How has Halo 5 done so far?

[Arkaign]

Halo absolutely declined for a number of factors.

The original fans of H1-3 are no longer teens and college-age kids with plenty of gaming time. They're adults with mortgages, commutes, kids, etc in most cases. Halo 3 was followed by the immense hit and growth of MW as the new 'event' game.

That's where Microsoft screwed up the most IMHO. Letting Bungie go, mishandling the IP from a franchise standpoint. Although I believe completely that it would have resulted in mostly worse games, adding a studio or two to the franchise and annualizing it was their only chance to keep up with the COD juggernaut. Putting many years between mainline Halo games simply let them be forgotten about and the hype faded away. Even worse when you had Halo 4 in there to kill momentum.

I think Sony is going to experience the same thing with Gran Turismo due to that similar but different mishandling. They go through massive gaps in releasing GT games, then strangely followed GT5 with GT6 too quickly, and on an outgoing platform when all of the massive hype/coverage/brainspace was focused on the PS4/X1 launches in holiday 2013. GT6 should have been delayed slightly and reworked as a PS4 game exclusive or cross-gen. As a holiday 2014 release it would have been a well timed pass-the-baton release. Nearly 2017 and no Turismo on PS4, and well, is a 17-year-old heavy gamer even going to know what Gran Turismo is in 2017-2018? 5 came out in 2010, so they would have been 9 or 10 years old at that time, and GT6 was barely marketed and I never actually saw it in stores (Walmart/Target/etc, you still to this day see the GT5 special edition or whatever at value price, but GT6 is a no show entirely).

Going too far without entries, especially quality entries, can damage franchises. Adults get onto other things, kids don't have any attachment or exposure to things that come back after eons, and well-timed releases take over (COD, Battlefield, even GTA is much MUCH better managed than Halo or Turismo's IPs).