Question about a PCP Warning

I have a couple of Custom/Private Plugins which use the 'required by'/'requires' feature in the headers.

PCB now gives the following warning for the plugin with 'requires' in the header which I do not understand.

Warning
– plugin_header_requires_plugins_not_in_directory
– The plugin declares "xxxx-xxxx" as a required plugin, but it could not be found in the WordPress.org plugin directory

The 'required by' plugin is installed and activated together with the 'requires' plugin and both work correctly.

Wordpress will not allow the 'required by' plugin to be activated unless the other is activated. The order of deactivation and deletion is also controlled.

Wordpress gives relevant information/guidance and warning messages on the plugins page for each stage of activation and deletion.

PCP isn't checking if the 'requires' plugin is installed or activated so what is this warning message for and why is it needed ?

The inference is that something is wrong because the plugin could not be found. This is misleading for an end user who might waste time chasing a non-existent problem.

Start by tracing the plugin_header_requires_plugins_not_in_directory warning and compare its wording with the described WordPress activation behavior. Confirm whether the warning is intended for private plugins, with done defined as wording or behavior that accurately explains the directory check without implying a nonexistent problem.