Can anyone enlighten me?

I am a new mom, who is lucky to get 4 hours of solid sleep each night. Jehovah's witnesses keep coming to my door despite me telling them that I'm not interested. There are usually two or three of them who come and their knocking on my door or ringing my doorbell wakes my baby. I even showed up at the door in tears, begging them to leave me alone, but they still come. Can someone, preferably someone who is a follower of the jehovah's witness tell me about the religion, and why they are so persistent. Maybe if I understood what they are all about, I would be more tolerant.