I need a word to describe this concept: correcting for individual stupidity when calculating scores for online reviews.
I've long noticed this on recipe reviews. Say there's a recipe for a dish that is overflowing with spices, then a reviewer comes along and says it's "absolutely bland and tasteless." I am forced to conclude that this reviewer simply cooked the dish wrong. Like, didn't have half the spices and so left them out, or had spices so old that they lacked flavor, or put in too much liquid, whatever. The thought that they fucked up never crosses their mind; no, instead let's log in and post a review saying the recipe sucks.
Similarly, of late I've been scoping out digital cameras, and I'm astounded at how often a camera will get good marks, four and five stars, and then there's one goober who gives it one star and complains about their problems. One that stands out was someone who wrote "This camera takes terrible pictures in low light," a comment that was not echoed by any other reviewer. I'm about 90% certain this person failed to turn on the flash.
The bottom line, I suppose, is that many people are idiots. Not exactly a news flash, I know.