A few years ago, Fernando Maciá, one of the most respected SEO veterans of the Spanish Search Industry, asked me to write the introduction for a book about Advanced SEO, which would be published a few months later.

In that introduction, I wrote: "SEO is not for the weak in spirit, but for those who know that every day I have to learn a new thing."

If I had to add words to that statement, they would be as follows:
"And International SEO is only for those brave of heart, because you never know which unknown territories you will discover with each project."

One of the many mistakes that SEO experts make in their work is reducing International SEO to merely a way to implement hreflang mark-ups.

Not that it is incorrect to do so – far from it – but it is incorrect to think that a website is ready to conquer international markets with only the use of hreflang according to the established rules.