Paying up

When buy /sell above / below value (i.e. paying up) you are obviously betting on the range expanding and that value will follow price and migrate. The PoC will migrate if there is an imbalance. So the question is under what conditions does an imbalance occur?

a) The mkt is in balance and ready to b/o - or stages a failed auction and breaks the other way.

b) The mkt is already out of balance - gap out of range or low overlap with prior range

b) One side is trapped - a la Oct 29.

d) No support / resist nearby - therefore no opposing activity likely