Why is a download manager frowned upon?

[Nehmo]

On http://www.backtrack-linux.org/wiki/...hp/Downloading “Do not use a download manager with our links as your download will most probably get corrupted.”
Why would it bet corrupted? Isn’t that the purpose of download managers, to get you an intact copy even if the process is interrupted?

[sickness]

The message is a recommendation, that means we have dealt in the past with people who downloaded Backtrack via a Download Manager and ended up with a corrupted version. You can use whatever download method you want, just don't come complaining to us if your Backtrack doesn't work afterwards.

[ugothakd]

And I think that goes for everything. If your computer is messed up because you couldn't check the md5, well...