Some people would like to see themselves as good people with good intentions but all too often their actions are actively counterproductive, a la The Shirky Principle that organizations tend to keep alive the problem they were created to address.
Some people just have broken mental models and then fail to update them when their efforts consistently prove "this does not actually work." We all make mistakes, but if you keep making the same mistake without any improvement, at some point others should stop making excuses for you.
Put Error to Work
> But let’s never, never, cover up error with the misguided thought that we must protect someone — either our brother, or our department, or our own pet ego. The recognition of error and its examination, if openly talked of, is a sure way to avoid its being repeated, either by the same man or by others. Everyone errs at one time or another. The Company pays for it. Okay. But the Company should not have to pay twice. Nor should other men be denied the benefit of warning-signs.
I think most people have good motives based on their world view and this will work.
Assuming good motives can help you uncover them.
For example the “asshole” at work who seems to be blocking you - they might have good reasons you can explore.
Of course their are liars, scammers, psychopaths. If possible cut ties otherwise you have to consider dealing with them tactically.
None if this is easy though!
But "When someone shows you who they are, believe them the first time" is also true.
... you don't have to assume, right? So I see no reason it is overly contradicting and would render that rule void.
Over here, to assume good faith is required by law to be the standard mode, you have to expect it otherwise society would crumble. IMHO you can't take and stress this far enough, and I can't imagine where it can be taken too far. But yes, please don't ignore your intellect.
It's a stock phrase, but it gained popularity online because of its use in Wikipedia. HN hadn't existed yet: https://en.wikipedia.org/w/index.php?title=Wikipedia:Assume_...
If you don't know their motives, assume good motives or good faith. But if they explicitly tell you they have hostile motives or the preponderance of the evidence suggests such, continuing to assume good faith amounts to cutting your own throat.