The profit from launching a master node is that you can provide services and earn from them. Master nodes will be able to earn from at least two sources.
The customer pays for using services provided by the validator - content delivery network, streaming platform, dedicated messenger, storage, cloud system, IoT hub, etc. Each transaction is levied a tax, part of which constitutes the first source of income for the master nodes. In addition to the validator’s fees, the service’s author receives an author's fee, and the network fee goes to the network development fund. The amount of the respective fees are determined by authors of the service and owners of the network.
The second source for master nodes to earn from are token emissions for stakers and liquidity providers. These rewards are set at a total of 3 million CELL for the year 2022, with halving of emissions every year there onwards (subject to governance voting).