Here’s the question and answer as read by John Mueller:“Charan asks: How to know if my SEO is perfect? Given that there may have been a language issue, maybe answering the literal question of “what is perfect SEO,” wasn’t the most nuanced approach. Just because you can’t do perfect SEO shouldn’t discourage you though!”A Less Disappointing AnswerMueller’s right that search engines and user queries are constantly evolving. So, another way to answer that question is to think in terms of what Google recommends as a best practice. Google makes that easy because it offers an SEO starter guide that breaks down the process of optimizing SEO into a series of steps that can become the basis of an SEO checklist to measure your SEO against.