Why do certain witches only worship the goddess?

I keep meeting witches who only worship the goddess and it kinda confuses me. I used to be a witch myself at a point in time and every witch I met back then believed in multiple gods and goddesses. I'm not saying goddess worshipers are wrong I'm just confused as to the why behind it cause I was always taught that witch craft is about balance. so please someone enlighten me it would be very appreciated.