Banking royal commissioner Kenneth Hayne. (Image: AAP)

Most royal commissions are too late and desperately needed. They're called as a last resort because of systemic failure in established processes and institutions, the kind that can't be fixed within the existing system.

Or, at least, they used to be. Increasingly, royal commissions are called for political reasons, to provide an out for politicians who have failed to do their jobs, who want to deflect responsibility, who want to show how much they care.

Daniel Andrews' royal commission into Crown might be way too late, but it's probably the most superfluous inquiry in history.