A soft brick is when there is an error in your phone software that prevents the phone from fully booting, also called a boot loop, because the phone keeps trying to execute buggy or incompatible software.
A Hard brick is essentially a full recovery, e boot (emergency boot), firmware, or kernel that was flashed. Incorrectly and prevents even simple hardware initialization.
Hard bricks you have to send the phone back (or from what I understand, a jig can be purchased), insurance I don't believe covers hard bricks and software modifications.
Your warranty is void now anyway.
Let's be honest, my dog ate your phone
Correct me if I'm wrong. Lol