To most photographers—those whose focus is on people and portraits, certainly, but also those who specialize in structures, food and products on location—the subject is the star of the show.
Location-based photographers know that the unsung hero of any successful portrait is the environment behind and around the subjects. Often, the environment offers clues and context that tells the story better than the subject themselves can.
In short, your backgrounds matter more than just as a place to put behind your subject.
Give thought to the environment around your subjects as deeply as you think about your subjects. Make sure that anything that shows in the frame is there for a reason.