Maximize Google's Search Quality Evaluator Guidelines to Propel Your Webpage
Are you worried that search engines will find the content on your website is the same as other content on your site? This happens frequently; sites that tickets for sale to annual events, the weather and more will have content that duplicates content that they have previously posted, with only slight changes.
Google is worried about copied content, not duplicate content. In their 2017 Search Quality Evaluator Guidelines, Google talks about punishing sites with copied content that don't add any value, even if the source is credited. Their algorithm takes into account duplicate content without any malicious intent. If you have content that duplicates itself, your not being punished when a competitor ranks higher than you, because if they are a competitor, they most likely have duplicate content as well.
Google does not like spun content or thin content that says nothing. Sites with high quality duplicate content do well in the SERPS. Numerous news websites publish AP stories word for word and Google understands this, so they will understand useful duplicate content on your own site. If you are legitimately offering useful content with added value, you don't have anything to worry about; Google is very good about weeding out bad content now, it rarely shows up anymore.
If your old content is no longer relevant, such as a job posting from two years ago, just delete it if there are no links pointing to the page. If the content cannot be of use anymore, such as an event that happened a year ago, and you're not getting any search traffic to the page, there is no need to keep the content. If you want to do redirects to a more relevant page that's fine, however, there may not be any more relevant content. The old content can just slow your website down as well.For more information click here https://www.reddit.com/r/SEO/comments/89b6c0/deletedcontentand_seo/.