One of my foreman called me this morining & told me I needed come meet up with them QUICK. When I got to the house I saw my newest employee with 2 fewer fingers than he left the shop with. I asked him what happened & he informed me he tried to change the height of the mower without turning it off first. We spent 3 hours in the ER, he got about 20 stitches shattered his ring & pinkie finger & lost both fingernails. Right now it is 50/50 if the fingers need to be amputated or not, we are going to a hand surgeon monday to find out. All because he wanted to save a couple seconds by not shutting the machine down before changing the cut height.