Dogs are great for home protection. The likelihood of them ever actually fending off a break in is miniscule, but just having company can be reassuring if you live alone. And their presence deters any would-be wrongdoers, even something so petty as neighborhood kids trespassing. Just make sure the dog doesn't BITE those neighborhood kids, or it could be your house.
When my family was moving out of our last house, we had already moved out before we closed on the house, some neighborhood kids decided they wanted to go jump the fence and take a dip in our pool. Our neighbors warned us about that and we called the police. They told us if a kid was to drown in our pool, regardless if they broke in, we would be liable. He told us what we could do is return the dogs to the house, we had two fully grown German Shepards. He told us if the dog bites them, we are liable, UNLESS we put us "beware of the dog" signs. So that's exactly what we did.
The next day, neighbors reported the same kids come back with swim suites and towels, saw the signs and hesitated, climbed up on the fence to look over and the dogs started raising Cain. The kids all ran.