I agree on the boom bust cycle, but if you're working the chain, once you become a certified electrician it is totally worth getting additional training on non residential things too. I don't know the lingo, but my general understanding from what my friends who are actually electricians tell me, is once you're licensed, its worth going the extra mile and piling on the extra certifications as insulation against market swings.

So for instance, one of the folks I know can do residential but also spent a year in the midwest learning how to wire up windmills. I guess that paid off in the last cycle when they had to pivot back and forth on jobs.

I just hate physical labor as a job, personally, but he makes almost as good of money as I do now, but my back will last past 50.