One of the scariest “first world problems” of technology that can happen while you’re traveling is when your phone is about to lose power. I mean, think of all the things you use your phone for when you’re traveling – travel documents, confirmations, membership numbers, addresses of places you’re going, maps, ride-sharing programs – SO MUCH! So when your phone battery is down to 2%, you want to charge your phone as much as you can as quickly as you can.
There are a bajillion (well, maybe not a bajillion. More like 3 or 4) ways to charge your phone but some will be faster than others.