I don't know everyone else's reason, but I am not a fan of those bulky extra battery cases, and I am not an "I carry an extra charger in my purse" kinda girl. So… when I'm out of juice… its just too bad for me… until now! I have finally found a portable charger that fits into my life… and my purse. This lightweight portable mini charger from Jackery gives me the full charge of those bulky portables, and extra battery cases, without the fuss and… well… ugliness that comes along with them. So bigger is always better… except for when it's not!