Apple should've been more upfront about throttling iPhones with weaker batteries (poll results)

Today's lithium batteries are rated for a certain amount of charge cycles before they start degrading in terms of capacity or ability to provide peak current. On the other hand, chipsets and other hardware are becoming ever more powerful and demanding, resulting in going over the fence when trying to extract stronger current from a weaker battery. This could result in phones employing shutdown procedures to safeguard the electronics in certain extreme scenario, so last year Apple smoothed out the peak battery demands by dispersing them over several quick cycles with the iOS 10.2.1 update. 

Apparently that meant throttling the processor's power, and resulted in 80% fewer iPhone 6 shutdowns, Apple reported at the time. It, however, kept this power management system in the next iOS updates, too, so once the battery in your iPhone 7 ages enough, it will likely become a bit slower and less responsive unless you crack it open and change the power bank with a brand new one.