Sometimes a site has been created in a WordPress Multisite network but needs to be moved to its own single site installation. There are a few scenarios where this might happen including:
The site has grown too large to be contained in the network.
In some instances you might find that you can move the site out of Multisite by using a plugin or a combination of plugins, but if this doesn’t work you’ll need to move the relevant database tables. Moving a site out of a Multisite Network in this way is a tricky process as it involves isolating the database tables in the Multisite database that relate to that specific site. However it’s not impossible.