If a download fails, next time an update for a release sees the partial download, it should delete it

I have my pc set to retain the downloaded installation files in a separate directory so I always have access to the original installation file should I need it for any reason. However, recently, I had a situation where a download failed, and when I reattempted download and installation, rather than delete the partial download file and begin again afresh, the application simply noted the installation file was corrupt and bailed. This forces a manual deletion of the bad download from the directory so the application can begin again. This just seems to be a cleaner way to handle exceptions.