When you copy multiple files in Windows Vista, the progress dialog gives you an estimate of the time remaining as well as an indication of what fraction of the operation has been completed. But one thing it doesn't tell you is the name of the file currently being copied. Why not?

The programmer responsible for the file copy progress dialog in Windows Vista explained to me that there were a few reasons. First, there's the problem of presenting information to the user faster than the user could read it. All those filenames flashing by made users feel like they had lost control of the computer, as if it had decided to go off and do something at lightning computer speeds. Everything was happening so fast that they couldn't keep up with it much less understand what was going on and be ready to stop it if something didn't look right. Users may have been conditioned by the Hollywood Operating System, in which a rapidly changing stream of file names usually means something Really Bad is going on.

Users also reported that the constantly-changing dialog felt unstable, like it never could figure out what it wanted to say. And of course it all happened faster than any human being could read it. There's not much value in presenting to the user information they can't read anyway.

On the technical side, there were slight performance benefits to suppressing the display of the file names. As we saw, updating the screen can be a significant cost when you are updating continuously. Furthermore, even determining what name to display for the file is nontrivial. It's more than just extracting the string after the last backslash, because you can configure a file or directory so that the name displayed to the user differs from the physical file name. This is important when dealing with languages other than English. On Chinese systems, for example, the file whose name is Calculator.lnk is displayed to the user as 計算器.

In Windows 7, the file copy dialog returned to showing the names of the files being copied, but only if you ask for it by clicking the More Information button. That way, the standard dialog looks normal, and only if you say, "firehose, please" do you get inundated with information faster than you can read it.