Google updates its search algorithm frequently. For example, on February 23rd, 2016, Google made significant changes to AdWords, removing right-column ads entirely and rolling out 4-ad top blocks on many commercial searches. While this was a paid search update, it had significant implications for CTR for both paid and organic results, especially on competitive keywords.
But sometimes there are site-wide technical issues that get in your way of ranking on Google. Luckily, fixing technical issues is not a required step for every single piece of content you create. However, as you create more and more content you should be aware of duplicate content, broken links, or problems with crawling and indexing. These issues can set you back in search results.