The problem with writing is that it’s wholly subjective. Qualitative. No hard data.
Where we can do quantitative analysis, we can make reasonable judgments even when our emotions aren’t in alignment. “I felt great about this today, but we actually had only a 70% success rate.” Or, “Oh, man, today has been a total downer and I hated this session, but we nailed it with a 90% success ratio.”
That’s very nice for behavior analysis and free throws. Not so useful with writing.