Meta descriptions, meta tags, keywords, alt tags, accessibility, mobile optimization, app implementation - these are just a small sampling of the elements on your website that need to be highly functioning and in proper shape for search engines to take you seriously.
You can create a DIY website, but you can't be successful without professional structure running your system. In other words, you could have the shiniest car on the market but if your gears were tinkered together by a toddler, you won't win a race. The same goes for the most beautiful person, without a brain, they can't move.
Harsh? When it comes to SEO business, we're stone cold serious.