Like 90% percent of the rest of the forum, I agree with your opinion on how capacitors aren't effective way solving some electrical problems, but a majority of the people outside of the forum aren't as knowledgeble about these topics. I believe you handled the interview in a less than professional manner, and you could use some improvement on verbal skills. The purpose of the forum members input is not to humiliate you, but rather to help you locate the source of the problem by means of constructive critism. If you don't get the job, it's not the end of the world, just do installations on the side for friends and gain experience from that. Best of luck to you.