One way to think of it is the stages of competence.
- Unconscious Incompetence - You're bad at it, but you haven't learnt enough to yet see you are bad
- Conscious Incompetence - You are bad at it, and now actually understand you're bad at it!
- Conscious Competence - You're getting better, but only because you're really applying your skills hard and putting in effort
- Unconscious Competence - You're good at it, and being good comes easily
2-3 is the low point where people tend to give up, because you go from that euphoria of being a new writer where you are cranking work out so fast and easily to the depths of self-loathing where even 1 page feels like a huge effort.
I feel it, because I'm there.
But this progression of skill applies to a lot of things in life other than writing. I work in IT and I've seen it there in myself and in others, so I know if I keep going then maybe one day 4 can be a reality :)