The answer to 'what causes bee' is that bees are attracted to a variety of factors in and around the home, including floral nectar sources, available nesting sites, and even food spills or pet food. Bees play a critical role in pollinating plants, but can become a nuisance when they build nests too close to human activity.
Common causes of bee activity include flowering plants, overripe fruit, sweet drinks or spills, and cracks or holes in the home's exterior that provide potential nesting sites. Bees are generally not aggressive unless their hive is threatened, but their presence can still be concerning for homeowners, especially those with allergies.