I have AT&T/T-Mobile/Verizon. Why do I need an eSIM if Puerto Rico is in the USA?

 For guaranteed speed and coverage. While your U.S. plan should work, it often relies on "partner" networks (like Claro PR), which can be slow (3G) or spotty. An eSIM often provides a more stable connection by locking onto the best local towers (like AT&T or T-Mobile's native 5G/LTE), ensuring your Google Maps works when you need it.