For many years I was a professional copywriter in LA. 

Traditionally, copywriters were the ones who not only wrote the words, they came up with the concept for the ad. Everything starts with concept. The toughest thing to learn is not writing. It is how to come with THE idea. That is what takes all the skill. 

In an ad, you aren't selling the product. You are selling the benefit. Once you click into that, you're 2/3rds there on understanding what advertising and marketing are all about. That's it; in that those five words: "you are selling the benefit." Selecting what benefit to sell is called strategy.

Of course there's a lot more to it than that. For example, we are all used to seeing certain things. We notice the unusual. When you see a person run a red light, you notice. But if we lived in a country where everyone ran red lights, it would be unusual to see someone stop. You'd notice and remember that. 

So in advertising, we are trying to get someone to notice something different in a sea of similar things called ads. So we have to do something different -- always, always, always -- something different that makes a pertinent point. Different, but rarely non sequiter.

For many years, McDonalds ads sold family. You can get your first job there. Work there after you're retired. Raise your kids there.

Nike ads don't sell shoes. They sell inspiration. 

In an ad, the question is what one point are we going to make to the target public to get them to accomplish the objective, i.e., buy one, come in for a test drive, try a sample, test it for 30 days, request more info, whatever. Let me stress: an ad headline must only make one point, not two. The analysis one what point to make is intuitive. Other points can be made in the body copy.

The onus is on the copywriter to make the public care.