SEO is Important
Your website should be easy for yourself to use, but most importantly for your users and search engine robots, to understand.
There are loads of errors that may occur on any website, should you not know your way around. It is no use having something YOU understand, but your users and search engines get lost in.
SEO will help search engines to know what each page is exactly about, so that useful info can be easily obtainable for others.
Automatic search bots crawls the web and follow links to have it indexed in massive databases.
Technical details of search engine-friendly web development is very important, but not enough. It is also important to continuously market your content. Search engines have no formulas to seep through the quality of content. It rather relies on metrics of relevance and importance, and they measure those metrics by tracking what people do: what they discover, react, comment, and link to. Building a perfect website with great content is awesome – but you need to share that content and get people to talk about it.