They aren't the best guard dogs.
Surprisingly, pities do not make the best guard dogs out there. These guys are inherently friendly with humans, and intensely loyal to their owners. Unless they are specifically trained otherwise, your pit would be ever too happy to welcome a stranger into the house. If you're planning to train her as a guard dog, it is recommended to do so professionally, as pits are stubborn. This will ensure that your dog backs off with a single command.