Because the private key needs to be guarded, its management becomes an important topic. If you need to decipher encrypted files or messages on a number of machines, you need a method to keep the private key safe.
First of all, if the private key file (secring.gpg) is somehow visible in a file system, then the administrator of that computer can “steal” your private key file easily. As a result, it is, generally speaking, not a good idea to make your private key visible to the file system of a computer that is not managed by you (as administrator or root).
On the other hand, it is safe to put the public keys in an exposed environment. This is because a public key cannot be used to decipher encrypted content.