No Mantra can be sold, nor can a Mantra be concocted, nor are there any new Mantras. There are specific Mantras that exist and there are no new Mantras. We cannot create nor can we give a different Mantra to every individual. That's the only secret. Initiation alone is not sufficient.
Initiation is just like igniting the fire.
It will go out. The match stick, the ignition, has no value then. Immediately after lighting the fire, you have to add more fire, to make it bigger and bigger and bigger. You and Siva, or you and Krishna, become one and the same. The more times you repeat the more the fire grows, bigger and bigger.