always against, so that blade approaches hair as close to 90 degrees as possible, cuts quickly and is done. what really kills the blade and creates cracks is w

always against, so that blade approaches hair as close to 90 degrees as possible, cuts quickly and is done. what really kills the blade and creates cracks is when you cut hair at 15-20 degrees and blade cuts hair and then starts dragging it along your face while cutting and this is how microcracks form and grow in size. you can create your own experiment with knife and some veggie like green onion. try to cut it at steep angle and drag it along the cutting board - and you will see that it produces much more stress on cutting surface