It alleviates that problem because your hand doesn’t have to grip the corners of the phone to be able to hold the phone with one hand anymore. You can pivot the phone from the center without dropping it or having to shift your grip.

If you can’t imagine it, seriously, it’s a $10 thing. Just try it. Give it a week for you to get used to it. If you hate it you’re not out a lot of time, money, or effort.