I attended a workshop about safe and respectful workplaces and one of the messages that was impressed on me by the presenter (a great presenter by the way) is that being nice can sometimes be very unkind to our fellow person.
If kindness represents doing the right thing, I have seen lots of people who are nice, but are not kind as they lacked the fortitude to do what was needed to be done. These people avoided conflict when they should have head it straight on. As well, some people use the shroud of niceness to hide their agenda or to avoid being held accountable. For example in my job in the health care field I have seen how being nice leads to taxpayer money being spent in ways that would make any rationale person cringe or have seen a nice, folksy senior manager turned out to be monstrous manipulator.
People might have good intentions to do the right thing, but make a citical error thinking that the nice thing is the same. Some people avoid the unpleasantness associated with doing the kind /right thing, and thus take no action. I guess this is why massacres and holocausts are allowed to happen and why “The Road to Hell is Paved with Good Intentions“.