The trouble with a glass back is that it can still shatter when dropped even if it has a case on it.
I’m not being funny. I treat every phone I’ve ever owned as the expensive devices they are. I buy a protective case, don’t put it in my back pocket where it can be bent or broken. I don’t use it while standing over the toilet so it can’t be dropped in. When I drink with friends, I don’t lay my phone on the bar where some drunk can spill beer on it.
It’s more than being able to have the use of a fully functioning device, at trade-in time my phone is worth more because I take of it.
Both times I've dropped the phone getting in or out of the car. First time it landed face first on the garage floor and shattered the screen and the second time it landed on its side and just scratched the case a little.
Hard to know what will happen when you drop your phone.
I find this is the real problem. I've had phones that I've dropped many, many times, onto hard surfaces, that have come away without a scratch. Then I dropped a Nokia 3 and the screen just flew apart.
I can't not drop things.