> You have two options - either get certified, so you can be trusted to carry out the work yourself, or get someone who is certified to at least look it over. Seems entirely reasonable.

That it seems entirely reasonable is most of the problem.

Because people imagine that getting certified is a two week safety course, and that getting inspected is paying someone $10 to spend ten minutes looking over your five minute job.

But then the licensed professionals capture the regulators and the licensing requirement stops being about safety and starts being about gatekeeping, so getting licensed becomes impractical for anyone not full-time gainfully employed in that industry. And the gatekeeping and bureaucracy cause the inspection to require weeks to get an appointment and the payment of $150 over the replacement of a $10 light switch.

Then, you notice that the light in your living room flickers sometimes. You would be inclined to have your buddy the electrical engineer come have a look except that he's not a licensed electrician and you're not convinced that the lights flickering once in a while is a problem whose solution is worth $150. Two months later the light switch with the bad connection finally overheats and your house burns down. Or you're willing to pay the money but it takes 15 days to get an appointment and the amount of time you had before the problem became a fire was two weeks.

Making repairs to safety-critical things less accessible is dangerous.