When Wing Gear Alternate Extension (free fall) mode is used, there is no hydraulic pressure to dampen the movement, sequence the operation or lock the gear in the down position.
Therefore the Wing Gear pressure operated restrictor check valve remains in the limited flow (closed) position for the initial 3 to 4 seconds of extension so the Wing Gear extends slowly initially, primarily to prevent the gear falling at an excessive rate and damaging the trunnion supports, due to the large moment arm of the strut, and secondly to ensure the gear clears the free falling gear doors.
Having done gear swings I can assure you, the gear drops like a rock and actually bounces until it's allowed to fall gracefully to extend fully we actually used to push gear at the end of travel just to help it along and lock down.