Why do people not like incinerate? Am I missing something?

I have incinerate and I push Tier 35-40 pit easily without, but anytime I have read anyone talk about it, it gets a shit tonne of hate.. why is the general opinion that it sucks? Is there something I’m missing?

The reason I am asking is, I have an eternal Sorc build and it was incinerate, and I was pushing high pit tiers, clearing bosses fairly easy, so I’m inclined to stick to that, but should I switch to lightening spear? I’m just interested to hear other people’s opinions on this, is the lack of crit chance and damage gonna be detrimental at some point I’m not at yet?