many pos systems offer this feature as time saver. Instead of having to perform inventory operation twice; a rough draft of the inventory item can be optionally created from the point of manual add at the invoice/register level. This would obviously need to be limited by role so that only an authorized employee can opt to add to inventory.

creating this feature saves time and becomes a huge productivity booster. One key boost in productivity is more accurate inventory as it removes the Ill do it later, after which, later never comes.

Additionally, this can be made even more versatile by adding the additional caveat that all employees can add to inventory if manually added to invoice. However, this would require an oversight mechanism to alert an admin level to the addition. Alert then allows the admin a chance to audit and correct before any error can get out of control.