One day you might want to transcode - compression artifacts may well not be audible in normal use, different compression algorithms drop different bits though a

One day you might want to transcode - compression artifacts may well not be audible in normal use, different compression algorithms drop different bits though and so the result of transcoding between compressed formats is quite often an audible (even to my distinctly non-golden ears) loss of quality. Thus FLAC (as a reliable lossless format) - or even WAV (I chose to take the 2:1, 3:1 compression of FLAC over WAV personally).