I think the word "brick" (technically speaking) is horribly misleading.
If you're doing anything with the firmware/software, whatever you do wrong is most likely temporary... that is, until you find out how to undo whatever you did wrong... or ask the good people of this forum.
...trial and error, my friend. I thought I "bricked" a couple of phones in my lifetime, lol.
Side note: my niece dropped my wife's phone in a bowl of water. It was in there for a couple of seconds before my wife saw it and took it out... after that, we heard sizzles and immediately turned the phone off. After we placed the phone in a jar of rice for 20 hours, the phone worked perfectly.
It's hard to "brick" a phone... just make sure you follow instructions.