SEO misconceptions

"The more visitors you get, the better your ranking will be."

Strictly saying: It's not true.

Example: If you run an advert and have a lot of visitors, it won't help you in itself.
Having more visitors in itself doesn't help your ranking. However, if you have a lot of website traffic because your page attracts visitors and they stay on your website, this could improve your ranking. If your so-called 'bounce rate' is low, it's a signal to Google that your visitors like your website.

"Paying ads in Google Ads will help your 'organic' ranking."

It's just not true.

If you run a Google Ads campaign, your website will be among the paid adverts highly likely in a good position. But it doesn't have any impact on your 'organic' ranking.
It might be worth considering to run a Google Ads campaign just for 'testing' your potential market, but it won't help with organic ranking at all.

"Keyword Density has to be accurate and perfect."

The truth: There's no such thing as the perfect proportion of content and keywords.

Of course, after analysing successful websites, you tend to draw a false conclusion, thinking: 'That is the perfect amount of content, that is the perfect keyword density'.
Yes, it is - in that particular case.
But given that every business is different, and SEO has many different elements, no-one can tell the 'figures' and the required proportions accurately.
Just create great content, be natural and write clearly about your topic.

Advice:
Don't squeeze (overuse) keywords. It's called 'keyword stuffing', and search engines don't like it. Neither do humans.

"After setting it up, you'll see the result immediately."

The truth: SEO is a long process. You won't get an immediate result.

The results you see when searching is not the 'live' internet. Search engine companies analyse and store the data, and the process might take weeks. The results which appear when people are searching come from the search engine company's web server. Every change on your website may cause a positive effect, but a website is never 'finished'. SEO is an ongoing process. Your website should be continuously maintained and updated. 

One of the important things you need to bear in mind is domain authority. This is an article from a brilliant SEO expert which you might find useful: How to Improve Domain Rating

You can read about more basic SEO principles  here.

"The more content, the better."

The truth: You should have the 'appropriate' amount of quality content.

The source of this 'myth': Websites which are successful in SEO contain much more content than websites of small startup businesses. When you look at these 'big' websites you could think: 'Oh, what a huge amount of words...'

Of course, you have to be quite 'active': Write useful and engaging content, be active on Social media, write articles and blog posts which are appealing. Be one of the bests in your industry in terms of your online presence.

As a result, your website will contain a lot of content, but not because you wanted to write so much of it. Having a lot of content is not the goal - it's just the result.