What could cause large flies to suddenly infest your home?

A sudden infestation of large flies in your home could be caused by several factors, including the presence of decaying organic matter, such as food waste or garbage, which attracts them. Open Windows or doors can provide entry points for flies, especially during warmer months. Additionally, breeding sites like compost bins, pet waste, or even stagnant water can contribute to an increase in their population. Identifying and eliminating these attractants is crucial to managing the infestation.