Many believe that SEO and Marketing are the same. If they do SEO, they are done with marketing and expect a result. And when they fail, they wonder why?
But in fact, SEO is part of marketing. First, you need to have a marketing plan and marketing strategy. Identify your target market, target audience, and maybe target country. Sometimes, you may even need to specify gender and age.
Think as a visitor not like a computer programmer. When you haven't heard about something, you don't search for that keyword. This applies to all other people. Doing advertising, posting blog posts and talking about the subject in social media will help people get familiar with your service or product and maybe later try to search for it. They may not remember your exact keyword, but remember the subject and search for that.
For example, you are a travel agency and provide vacation tours in one of the beautiful cities of your country. That city might be well-known in your country and you want to attract foreign tourists to show them that beauty. But what if no one in your target audience has ever heard the name of that city? in that case using the name of that city in your keywords is not correct unless you do a wide social media marketing first.
Without any clearly calculated marketing plan and marketing strategy, your SEO efforts may cause a waste of your time and money.