These masks are sculptural gesture drawings. By gesture, the artist means direct, without over-thinking.
That doesn't mean they are quick--that flash of response saying this mask wants to have, for instance, a thinner exhaust pipe section requires cutting, bending and welding. Even when that alteration is complete, another may be needed--it may still not feel right. This face wants to be brought into the world and I have to be a midwife with an angle grinder and a MIG welder.