The ultimate goal of wrestling is not pinning, it is to simply score more points than the opponent. I agree that back exposure should be worth more points though.
Passivity:
does not attempt or execute any holds.
is satisfied just to neutralize the opponent's efforts, blocking holds.
gives the impression of not trying to initiate effective holds.
intentionally "plays the edge," flees the mat, or pushes the opponent away to avoid wrestling.
holds the opponent by one or both hands to prevent him or her from wrestling.
repeatedly fakes head throws; slips off; falls to the mat; lies flat on his or her stomach; locks his or her legs around the opponent's leg.
in Greco-Roman wrestling, engages in combat with head thrust forward in order to prevent "body-to-body" contact.