Why did Apple Music lose all my album art from iTunes?

You had album artwork which was retrieved in iTunes, how/why did you "lose" it for Apple Music? Album artwork that was retrieved under iTunes is now showing as "unable to find" in Apple Music... Not a very successful adoption/conversion to a "better" program!! Existing artwork should never be lost in when the same music library is used (especially that which was programmatically obtained in previous iterations of your application), unless you have intentionally chosen to not resognize music that has been published and released for years (Example: Lynyrd Skynyrd "Southern by the Grace of God [Live]", Pink Floyd "Echoes, The Best of Pink Floyd [Discs 1 and 2}", and Red Hot Chili Peppers "Stadium Arcadium: Jupiter [Disc 1] and Mars [Disc 2]" - and yes, I bought and still own the CDs of every one)...

Thanks.