Cooking Eggs Too Long Ruins Their Flavor
The longer you cook an egg, the more flavor and texture you lose. Overcooked eggs become dry and rubbery. Crumpling yokes and flavorless whites will add nothing to the taste of your salad.
Not Cooking Eggs Long Enough Is a Health Risk
Not cooking eggs long enough can increase the risk for diseases like salmonella and food poisoning. You'd hate for your salad to make someone sick. If you are leaving your salad out for any length of time, the risk of illness is further increased.
Covering the eggs with one inch of water, bring them to a boil. Remove the pan from the burner. Keep it covered and let the eggs cook in the hot water for 12 to 15 minutes (12 for smaller eggs; 15 for larger ones). Inspect the eggs before adding them to the salad; the yokes should be cooked through but still moist.