If you are using a content management system or any web-based software, then it essential to keep it updated with the latest security patches and bug fixes. You don’t have to be running an e-commerce site for hackers to want to break into your website. Hackers will break into a website and upload Trojan and malware for use in their other attack schemes.
One of the primary ways hackers gain access to a site is through out of date software. As security patches become available, hackers will try to take advantage of websites that are not constantly updating the software on their sites. The last thing you want is for your visitors to get infected by software downloaded from your site. If Google detects malware on your website, they will de-list your site until you get it fixed.
So maintenance of a website is like oxygen to it. The site should be periodically updated in terms of security patches, plugin updates and content updating for SEO. Google crawls the websites with unique content and enlist the website in high searching indexes. The content of a website ensure the existence in the market and everybody gets the information you want to let him know.