Moz contributor Rand Fishkin points out that in the past few years alone, SEO has undergone several changes. Search engines are always changing and evolving for the better to provide an improved search experience for users. Google, in particular, understands that their users are more interested in finding quality and engaging content, and their numerous algorithm updates have made Google searches as natural as asking someone a question.
With the gradual evolution of Google comes changes in SEO, and some tactics which might have worked before might not work now. Hence, you need to hire trusted SEO services that can implement the latest strategies meant to improve your marketing efforts, and so help you stay on top of results pages.