Why is my migration status table empty? I wanted to delete all migration modules because of that I use

drush config-delete migrate_plus.migration.ID


After that, I create a new migration module and enable it with 

drush en migrate_NAME


and rebuild the cache. 
I look at the status table with 

drush migrate:status


but the table shows no migration. If I enable the migration again I get the message "Already enabled". When I try to import something I get the message "No migrations found".
Does anyone have any idea why this might be?
I think that you are mixing up things. By doing

drush config-delete migrate_plus.migration.ID


you are just deleting migration_plus configuration but you are not disabling the module, it is still enabled. If you really want to disable the module and of course the configuration, you'll have to drush pm migrate_plus.

Concerning the "No migrations found" message, your custom module has to define correctly the new migrations (.yml files).