Been using cutoff wheels for 20 years. Always leave the guard on and keep my cuts at an angle where it won't fly off into my face. Never any issues. I probably have more brain my damage from welding fumes on galvanized and thru paint
Had a buddy put an angle grinder through his femoral artery. Don’t remember what led up to it but result was running grinder in his thigh.
he was on the floor working on a car in his garage when it happened. Phone was on the bench and he couldn’t stand up. Statlrted scream for his wife in the house. No response. Fortunately the garage was on an alley and a hang out place at night. Someone drove by and saw the lights on and stopped. Called 911. Could have died.