Why is Windows so slow?

This is just venting.

I often have to transfer files to remote Microsoft Windows servers, connected via VPN and RDP. My broadband connection is a bit slow - my uplink speed is often only 500-700kbps and sometimes only 200-300kbps, though rarely worse than that.

If I zip the source folder, which takes less than 5 seconds, I can copy it to the remote system in about 3 seconds and unzipping to the destination is sub-second. A total of about 30 seconds, including opening explorer, navigating to the source and destination folder, etc.

If I copy and paste the folder using Microsoft Windows explorer functions, it takes 5 to 15 minutes to transfer the same data. It takes a minute or more to complete the copy, traversing the few directories to find the few hundred files. Then many minutes to paste the files to the target on the remote server. The uncompressed data is less than 5 times the size of the zip file so even if RDP doesn't compress data through the pipe it doesn't come close the explaining the performance difference.

I can't imagine what nonsense Microsoft Windows Explorer is doing that it takes so long to copy then so much longer to paste a few files. Certainly not anything of any benefit to me. And certainly not anything necessary, given the few seconds it takes to transfer the files in the form of a zip file.