The winds picked up a fire started by poor forest management @DB
The Camp fire looks like it started on private property from a PG&E power line problem.
Any ignition source this time of year coupled with very high winds will be an inferno. Period.
Now, I'm not saying California hasn't done a lot of stupid things with its environmentalism laws/rules. It has.
But the Camp fire was huge because of a combination of location, very dry ground, low humidity and very high winds.
Regarding prescribed burns, they still occur in California in the area I use to live - but - it was kind of a running joke there. About half the time they started a "controlled" burn it went out of control and burned a lot more than intended. Mountains and sudden shifting winds are a tough environment to control fire in. Embers can float off and start spot fires far away from the original fire source.