If you believe you can permanently delete any data by using the shift and Delete keys, you are mistaken. By using the shift key and the delete key, you have performed a hard deletion, which can be easily recovered by using third-party recovery software.
For permanent deletion, users can go with NetforChoice Data Erasure Software, which offers permanent data destruction that is beyond the scope of recovery. The software overwriting the storage device value with 0 and 1 makes it impossible to recover deleted items.