[Gordonjcp]

Deliberate barrier to entry.

If you're going to use something that needs a bit of technical skill to operate correctly, you're going to need at least enough skill to get it running.

Roads would be far safer if every car had some facility by which you had to remove and refit some random engine or braking system component correctly before it would start.

[zamnos]

Would roads be safer, or would there be more mechanics? They seem like different skills.

[Gordonjcp]

Roads would be safer, because people would understand more about their car that "PUSH BUTAN GO FAST"

[CapstanRoller]

Everyone would be too busy wrenching on their cars to drive them

[Tao3300]

Roads would be more dangerous. I put the work into my car, I'll drive how I want.