1: 1. Overmixing the Meat 2. Not Seasoning Properly

2: 3. Pressing the Patties Down 4. Cooking at the Wrong Temperature

3: 5. Flipping the Burgers Too Often 6. Using Lean Meat Only

4: 7. Not Letting the Meat Rest 8. Using a Dull Knife to Cut

5: 9. Not Preheating the Grill 10. Overcooking the Burgers

6: 11. Overcrowding the Grill 12. Not Using a Meat Thermometer

7: 13. Skipping the Toast 14. Adding Too Many Toppings

8: 15. Flattening the Burgers 16. Not Waiting for the Grill to Heat Up

9: 17. Using Frozen Patties 18. Keeping the Lid Closed Throughout