Simply because the errors when re-ripping sound differently, which is one of the whole niceties, of vinyl records. (for a non-aficionado it might be difficult to understand, I know)Ripping from CDs is a different thing, though: If you are too lazy to rip a CD to a lossy file whenever you need one (usually you would do this just once), you can rip it to a lossless format of your choice -- I suggest FLAC