As part of a multi-network WordPress instance there is often the need to quickly access the administration pages for WordPress. This is especially useful on a local environment such as valet or VVV where you may have multiple WordPress sites on a variety of WordPress instances and versions.
The use case for this extend onto production and staging environments also. For example we use this on our main site to keep it inaccessible. You could also activate it on an in development sub-site which has not yet been setup.