Lead sources are created at the same time that leads are created in kvCORE. In many cases you might be trying to setup something like lead routing, only to find that your sources don't exist yet! The source can be something that is defined by you (like when you are building a landing page), or if the lead get to your website in another way, the system will create a source name as best it can.
Have more questions? Please reach out to Customer Support via the blue chat bubble to the right or by emailing email@example.com!