Anyway, eventually I found my way to a page about the Dunning-Kruger effect. Have you heard of this?
The basic theory is that when people are incompetent at something they tend to lack the ability to realize it and they overrate their abilities relative to others. Meanwhile, people who actually are good at something tend to underrate their abilities and may as a result suffer from lack of confidence.
It got me thinking of all those insanely talented writers out there in fits of despair thinking they're not any good. Could it be that they're just suffering from a little Dunning-Kruger effect?
Take it away Wikipedia!
The Dunning–Kruger effect is a cognitive bias in which "people reach erroneous conclusions and make unfortunate choices but their incompetence robs them of the metacognitive ability to realize it". The unskilled therefore suffer from illusory superiority, rating their own ability as above average, much higher than in actuality; by contrast the highly skilled underrate their abilities, suffering from illusory inferiority. This leads to a perverse result where less competent people will rate their own ability higher than more competent people. It also explains why actual competence may weaken self-confidence because competent individuals falsely assume that others have an equivalent understanding. "Thus, the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others."