It’s one of the biggest factors when judging trustworthiness:

• Was the content thoroughly checked by the publisher?

• If so, when was it checked?

There’s no reason to trust content that the publisher will see only after millions of others have already seen it.

1. MORE trustworthy: content that was “pre-checked”

• A person on the publisher’s staff checks every bit of content BEFORE the content is put before the public.

• The typical newspaper is an example of thoroughly “pre-checked” content: everything that is published is first approved by a person on the publisher’s staff.

2. LESS trustworthy: content that will be “post-checked” or will remain “unchecked”

• No person on the publisher’s staff checks the content until AFTER the content is put before the public (if it is checked at all).

• Most* areas of social media platforms are “post-checked” or “unchecked,” meaning that almost nothing that is published in those areas is first approved by a person on the publisher’s staff.

*The biggest exception is material on social media that is published by sources committed to “pre-checking,” like news organizations.

See also this brief.