Yeah, I think he was referring to lossy compression schemes will never be the same quality - obviously since it's throwing away information, although usually what you're ears (or eyes in the case of JPG or videos) are least sensitive to, so the majority of people won't notice the difference.

Lossless compression is always the same quality as the original, except it has the overhead to converting back as well, which should be fine/not noticable for audio or other uses that have only require a low bandwidth to seem to play back seamlessly and on a fast enough computer.