Deleting a template will permanently remove it from your workspace. You will lose all information contained within them, previously created forms and any associated analytics references.
Note: We strongly recommend you do NOT delete templates as this content may not be able to be recovered. Alternatively, you can archive templates to move them out of your 'Active' library, without losing any previous records. (Here is an article on how to Archive Templates).
In order to fully delete a template, you will first need to archive it.
Steps:
Go to the Home Folder, then click Template Library
Select the checkboxes of the template(s) you wish to delete
Click Archive
Select the Archived Tab
Again, select the checkboxes of the template(s) you wish to delete
Click Delete