https://wccftech.com/iphone-x-battery-life-reduced-two-years/

Smartphone battery degradation is imminent. The only way you can minimize its deleterious effects is to improve your charging habits or replace the battery. For iPhone X users, it looks like a battery replacement looks to be the only way to restore performance and improved screen-on time, as some users have gone on forums, complaining about how bad their experience has been.

Users on both Apple Support Forums and Reddit have come out saying that the iPhone X battery life has dropped to a point where they are concerned if they should head out for a replacement or not. One user reports that the iPhone X keeps shutting down after it has reached 20 percent of remaining battery capacity.