Some people will see your cameras and think that they might have a way around them. They might try to destroy or remove the cameras. Some people might even try to steal the cameras, not realizing that the footage is not actually in the camera. Even animals can tamper with the camera if they are curious. It is usually a good idea to have some method by which you can reduce their tampering to a minimum, as well. You have some good options available.
Some of the most popular options are lockable enclosures and cages that are going to protect the camera. Cabling can help to keep the camera housing where it belongs, as well. They will be able to ensure that no one and nothing will have easy access to the camera except those authorized for it.