Clean download directories

[prairiedock]

I don't understand the operation or purpose of "clean download directories". I understand it may delete files previously downloaded, but I don't know when or why.

If space on the downloading computer is not a problem (nor space on the iso or usb stick), why would I ever want to check "clean download directories"? Couldn't I just let updates accumulate in the download directories, since what is installed on a target system is always determined by the requirements of *that* system, as determined at the time of installation?

In other words, is "clean download directories" just to save disk space, or is it to prevent the installation of old or obsolete updates?

[-Iwan-]

"Clean directories" means: if an update was replaced by an other update and if the old one is no longer needed, the old one will be deleted.

[prairiedock]

Thank you for the succinct reply. Let me ask one more question to draw out the implications of this.

If I check "include service packs" (assume Windows XP), WSUS OU will download XP SP3. If, the next time I run the update generator, I UNcheck "include service packs" while checking "clean download directories", WSUS OU will DELETE the downloaded copy of SP3.

(*) This is because since it is no longer in a position to supply a LATER service pack for XP (if there were to be one) because "include service packs" is no longer checked, and because WSUS OU always aims to provide only the latest updates to the operating system, it declines to keep a possibly obsolete update (XP SP3). (Yes, I understand that SP3 is in fact currently the latest and probably last service pack to XP.)

Is (*) correct? If it isn't, how would you explain it?

Thanks again, prairiedock.

[aker]

If you uncheck "Include Service Packs..." WSUSOU adds the service pack to the internal exclude list for downloading.
That means WSUSOU it wont be downloaded. But the same exclude list is used for cleaning up.
It is listed as unneeded an will be deleted.