Well, with this last one they finally made the telephoto 48MP. Also, vapor chamber is nice. I don't know if the 18 will have enough for me to upgrade, and it might even have a reason for me not to upgrade (removing gestures from Camera Control). But so far it's been every year, because I've only been using iPhone for a couple years, and my first was a refurbished 15 Pro Max.

The 17 Pro (non-Max) only comes with up to 1TB of storage, but that's still more than my 15 of before.