Cracking root passwords

How many people here usually crack the shadow file on machines they;'ve rooted on HTB?

I was watching an ippsec video and he had the root password for Nibbles> I was thinking about trying to crack one of the active boxes passwords just to have for a redirector if needed (for example to use on Sense if I don’t want to reboot it.

Maybe cracking shadow is just waste of time?
if i am not wrong the shadow file contains SHA512 encryption… and i don’t think it will be easy to crack xD