I don't wish to denigrate vbscript in any way, I probably should use it more, the results are certainly easier to read than some of the stuff I do. For the record, I had to schedule a job to delete old files and a quick look up in the operating system help and I did this:

Forfiles -p D:\backup /m *.* /d -21 /c "cmd /C del @Path"

I titled my scheduled job RemoveOldBackups so I still have some reasonable idea of what this line does. (I just used 21 days to match the example provided.)