Respectfully, nkedel, these are two different things. When I buy a new car, the manufacturer provides me with an owner's manual which sets forth a maintenance schedule of such things as oil changes. I have seen the documentation for new computers from Sony, Toshiba and Lenovo (and perhaps others as well) and I have never seen one word about maintenance, particularly file deletion.

This is your field (you're an engineer, if I recall correctly) so you know these things. If a company expects me to, e.g. delete the contents of C:\Windows\Temp they should tell me when, how and why.

Without such instruction I think it is indeed unreasonable to expect the customer to do so. How would I know that otherwise?