When fish lose the slime layer and touch the ground, the ground contact can introduce many forms of bacteria and fungi to the exposed skin/scale area. You may have had a problem in the past, you just never saw the results of dead fish. The removal of the slime layer becomes more important in contributing to deaths depending on several factors such as how soon fish can get ample food to replace slime layers, water temperature, length of time out of water, types of bacteria, fungi, virus, on ground, amount of human handling, conditions of transfer, and amount of stressors after stocking, in-pond stresses can be numerous and varied. Allowing a fish to touch the ground out of the water is basically a death sentence to that fish. Only a few are able to survive that "rough" handling. When people drain a pond where they have been stocking numerous larger fish over the years, they always say "What happened to all those fish I put in there?"
