If you want to drive visitors to your website, you constantly want to be engaged with your content. Top search engines like Google update their algorithms very frequently (*last update*: Google BERT, Oct 2019.)
Making content rank in Google is like trying to get a word in with your loudmouth uncles during the annual Christmas dinner – you need to keep a close watch and when you see a hopeful gap, you seize the opportunity. If you don’t, the entire table will forget about your existence.
More, users’ needs change. New problems arise and the first to solve them with helpful content (hopefully you) will reap the rewards.