Interesting how many fires were Volvo's. Maintenance plays a big part, but proper engineering and quality construction plays the biggest part.
Obviously this fire Bob is discussing is from poor engineering, running a large capacity wire unprotected through an open axle bay is asking for trouble and they found it. You dont have to be a licensed engineer to properly build things. Its all in books and its all basic stuff anyone can learn. How many of us have seen cars with stereo and other electronic junk wired so poorly its amazing more dont burn to the ground.
There are basic mechanical practices books on Aviation available at many libraries, that show accepted practices for routing and configuring of electrical wires, conduits, plumbing and hydraulic lines, wires and hoses. They show proper fastening and construction techniques of metal and wood and fabric, bolt and fastener size charts, soldering and bonding practices, etc., etc.. Its basic material and information thats been known and taught for almost 100 years. Its not that much more expensive or difficult to do it right, its just a little more time consuming which all too often these days is being sidestepped for profit.
When we were wrecking Buses, my Father who was a retired aircraft mechanic, pointed out a lot of construction details he saw on the older GMC's, especially the wiring, that more resembled an aircraft than any other machine. And 95% of it is buried away in the bowels of the Bus where it will never be seen until it is de-constructed. Its a testimony to that level of quality and engineering that so many are still on the road today.