The waste hose on washing machine sits on floor/low
Yes there will be a little stagnant water but there always is the pump is in the bottom of the machine and it can only push water out as long as there is water to push when the pump stops the pipe is still full any extra pipe on the ground will add to that amount but a couple of inches won’t be more than a cup or 2 added to what is there no washer that I know of empty’s that last quart or so of water.