Article: Hanlon's razor
Hanlon's razor is a heuristic suggesting that when assessing people's actions, we should not assume their intention is malicious, as long as there's a reasonable alternative explanation. As Napoleon Bonaparte also said: Never ascribe to malice that which is adequately explained by incompetence.
While Hanlon's razor and Napoleon suggest stupidity and incompetence can be the reason, I like to use "Charitable guess" more and find every possible (doesn't even have to be too reasonable) explanation to make the intention neutral or even good.
Like in the example I gave in This is Water, we can always be annoyed by the inconsiderate aggressive drivers cutting our line while driving. But we can think in different ways. Those who cut us off are driven by a father whose child is severely sick and needs to be in the hospital as soon as possible. They are in a more legitimate hurry than I am, and it is actually I who is in his way.
Of course, Hanlon's razor and Charitable guess don't imply that their intentions are never malicious. Nonetheless, even if our assumption turns out wrong, it can still be useful by channeling us to avoid negative emotions associated with assuming bad intentions. Again, wrong but useful as Weekly I/O #32.1 and Weekly I/O #34.5.
Also by Hanlon's razor, "don't invoke conspiracy when ignorance and incompetence suffice, as conspiracy implies intelligence".