The answer to 'why is my cockroach swarms' is that you likely have a severe cockroach infestation in your home. Cockroach infestations can lead to swarming behavior, where large numbers of cockroaches become visible, especially at night or in dark areas. This is often caused by an abundance of food, moisture, and harborage sites that allow the cockroach population to grow unchecked.
Cockroach swarms are a clear sign that you need to take immediate action to eliminate the infestation. Cockroaches can spread diseases, contaminate food, and cause allergic reactions, so it's important to address the problem as soon as possible. DIY methods like using baits, traps, and insecticides may help, but a severe infestation may require the expertise of a professional pest control technician to fully eliminate the problem.