AP vs Traditional (Support)

This has always been a very controversial topic, in my opinion. It varies by champion. To clear this out of the way, champions like & I always build tanky, no matter what. But, for champions like , , , , , I usually build AP/Support (Whoops, ignore blitz, I build him ap/traditional/tanky).

Why, might you ask? Honestly, for a champion like , I feel like I'm benefitting my team more with AP (More damage boost to the target champion for my E, and much more of a live-saving heal). Same thing with and , my heal heals for way more with AP than it does traditional. It feels like a sort of fuzzy tickle without AP. Along with , why would I build traditional (Speed boosts, an itty bitty shield) when I could be doing more damage with my q/e/ult (I understand that I am not looking for kills as a support), I just feel more useful building AP. I feel like I'm doing something for the team.

Although, some of my teammates get angered by me being building AP instead of traditional. I don't understand. I've always seen traditionally-built supports that become squishy late game ( , , ), but I've performed better than said squishy supports by building AP.

So, my real question is (I guess), what do you build and why? I understand it depends on the champion, but, I haven't quite ever understood building traditionally on a support that can benefit a lot better from AP.

Yes, I do build on my supports (sometimes, depends on our performance. Yes, yes, I know is key. I get a little lazy sometimes) regardless of if I'm ap or not. Along with the .