Cryptocurrency purists often dismiss private blockchains as overly expensive undertakings for projects that are better served with a traditional database.
Yet these distributed ledger solutions keep being rolled out by enterprises in various settings – mostly still in experimental phases, but, increasingly, with real money at stake. And while they fall short of the public blockchain ideals of censorship resistance and permissionlessness, these contained, private experiments are extremely useful to the development of the overall blockchain industry.
https://www.coindesk.com/the-power-of-private-blockchains-is-beginning-to-show/