It's more like I'm going out for a walk and I pick up my phone to spot that the battery is at 15%. I used to put it on charge and the walk would have to wait ( well, the dogs I was walking would have to wait more specifically). Now I can charge it and go for the walk at the same time.
I think it's probably designed for people who are camping for a few days with no electric available, but it works for forgetful people like me, too!