Why the RNLI remains a volunteer charity

Why does the government leave lifeboat rescue to the RNLI instead of running it directly?

The volunteer and donation model makes nationwide rescue financially viable, whereas a fully paid government service would be much more expensive.

The Royal National Lifeboat Institution is a charity rather than a normal government department. Its volunteer crews and charitable donations sustain a service that would be extremely costly to reproduce with public employees. Government therefore has a strong interest in ensuring the institution remains viable without directly operating it. Maritime safety in this case depends on voluntary action backed by an implicit state interest in the charity's survival.