Nor does being emotionally labile translate to artistic insight.
Many visual experiences — particularly those on a large scale — evoke an emotional response (but I hardly have to add that not all impressive visual experiences are art). It's no mistake that so many abstract painters work on a gigantic scale; scale all by itself is visually stimulating.
After that, an angsty personal biography is a must.
Interesting choice of words. What is intriguing about many abstract impressionists is an ability to translate rather faithfully an emotional instability (or perhaps less derogatory, an ever-changing emotional state) into an ever-changing or unstable visual image. Perhaps it is the very mutability of the final image that separates the good from the bad in abstractions.