If your lift has no sensing plate then adding one, or building a surrounding barrier around the lift would be wise. Look under and see if there is a suspended plate or rubber nosing under the lift. If so, while the lift is moving down, press up on the nosing or plate with a broomstick inserted from the side away from the lift. It is apparent that these safety aspects considerably affect the homeowner's liability, should any accident occur. While we are discussing a residential outdoor application, lets look at other environmental factors.
Acid rain is a fact of life.
Rain, driving wind, and the neighbors sprinklers make it important that the lift controls are both waterproofed and connected to a ground fault interrupter. Options should be explored for various finishes. Lifts only really work well where they are installed plumb and true. Please seriously consider a substantial concrete pad under yours, with appropriate drainage. Dirt, bricks, wood, patio blocks just don't get it done.