do you mean you have created tables called "drivers, driver1 etc" and now you want to get rid of tables and their associated data? Are the folders created under "/usr/hive/warehouse" directory? Have you used the following?
DROP TABLE [IF EXISTS] table_name [PURGE]; --> DROP TABLE IF EXISTS drivers PURGE;
If your table is not a hive managed table (data under hive warehouse directory) or in other words when you create an external table, then dropping a table does not delete data. Data is deleted on drop table only for Hive Managed tables.
I completely understand the concept of external table . But what i was looking for is, What are the reasons when a 'Managed Hive table' is dropped but the data underneath hive warehouse directory still exists.
Are these tables External Tables? In the case of external tables you would have manually clean the folders by removing the files and folders that are referenced by the table ( using hadoop fs -rm command)