Maggots in trash cans are caused primarily by flies that are attracted to decaying organic matter like food scraps. Flies lay their eggs on this rotting material in the trash, and when the eggs hatch, maggots (fly larvae) emerge and feed on the decomposing waste. Factors that contribute to maggot infestations include:

• Presence of exposed or poorly sealed food waste in the trash.
• Warm, moist, and humid conditions inside the trash can that accelerate maggot development.
• Garbage cans with loose-fitting lids or broken seals that allow flies easy access.
• Odors from rotting food that attract flies to lay eggs in the trash.

In summary, maggots appear because flies find trash cans with food scraps to be ideal breeding grounds due to warmth, moisture, and odor. Proper sealing of food waste and maintaining clean trash cans can help prevent maggot infestations.