It's not about being disgruntled, it's about not wanting your family to go hungry because you were only able to deliver three hundred packages in ten hours by taking extra care.
There's a difference between destroying someone's stuff because you hate your job and just not caring about someone's stuff because you want your job.
That exact same argument would hold true for drug dealers, mob enforcers, and a whole variety of people that do bad things. Sure, the mob boss is a bad guy for having the enforcer break someone's shop up; but the enforcer is _also_ a bad guy for doing it.
If the mob boss holds leverage over the enforcer (first a debt with threat of violence, and later evidence of the enforcer's crimes) then the enforcer might not be such a bad person. This is a big reason that lower level criminals are offered witness protection in exchange for information
Taking actions that you know put someone else's personal property at risk _is_ malice. It's less malice than actively breaking it, but it is actively making a choice to put something that belongs to someone else in harm's way.
No, it's not. Neither is minor speeding, for example. It's a lack of care and awareness about the consequences of one's actions - hardly a desire for those consequences. You say "active" and the whole point is that it isn't.
> There's a difference between destroying someone's stuff because you hate your job and just not caring about someone's stuff because you want your job.
What is the difference, when you said you destroyed the packages in each case?
But, the results are the same in either case. People's property gets destroyed. If the results are the same, what is the actual, real-world difference?
It depends on your angle. If your looking to solve the problem, the root cause very much informs the solution. If your looking to prosecute, intention and context often inform the severity of the charge(s) and determination of guilt (ie man-slaughter v. first-degree murder).
There's a difference between destroying someone's stuff because you hate your job and just not caring about someone's stuff because you want your job.