By default, users who can Publish into a Resource Folder also have the ability to Delete files from that same folder - be it the files they uploaded or any others.
There is however a setting in Admin > Settings where you can change this so that only Main Admins of the platform have the ability to delete.
In Admin > Settings find the Resource Delete Permission option under the Resources section:
If the default is changed to 'Admin', the setting will restrict the ability to delete items to Admins of your Folders. So Publish-level users still have their regular permissions to upload files, but can't delete items.
This setting will apply to all Folders on your platform.