How do my locks get dirty?

Any lock collects dust, dirt and filth as time passes, because it is near your door handle, which nearly everyone touches as they pass to and fro a room, and now, with this virus in the world, we are more aware of it than ever.  Failing to clean your locks means that this dirt becomes hard around your lock, making your locks hard to use.  It is also matter of safety to keep your doors and locks cleaner than ever now.