I have seen many webmaster complaining about the loosing position after getting desired rank. So here is the quick tops for maintaining it.

Do not stop the link building activity but reduce it to certain percentage and focus much on the quality

Regularly update the content even after getting rank

Regularly share your updated content in social media sites

Yes i completely agree with you.If we get our desire rank so it does not mean that our work is over.In seo we need to perform work continuously to maintain our ranking position.

Hi Friends,
Ways to maintain your SEO ranking

• Update your site. This sounds intuitive, but it's one of the most common mistakes in the internet marketing niche.
• 
  Speed up your site.
• 
  Expand your link building.
• 
  Outbound and internal links.
• 
  Build your social media presence.

You may maintain your website after getting rank to follow the terms of link building.

Update your site. This sounds intuitive, but it's one of the most common mistakes in the internet marketing niche. ...
Speed up your site. ...
Expand your link building. ...
Outbound and internal links. ...
Build your social media presence. ...
Closing thoughts.