Why Arizona has no cap at all
Arizona Constitution, Article 2, Section 31 states plainly: "No law shall be enacted in this state limiting the amount of damages to be recovered for causing the death or injury of any person." This isn't a statute that could be repealed by a future legislature — it's a constitutional guarantee that would require a voter-approved constitutional amendment to change. Arizona is one of only five states with this kind of protection.
This applies to economic damages, noneconomic damages (including pain and suffering), and punitive damages against private parties alike. The one real limit involves government defendants: punitive damages are barred entirely against public entities and employees under A.R.S. §12-820.04, though compensatory damages, including pain and suffering, remain uncapped even there.