Faulty CD

In simplest terms: The music data retrieval and usage method for music reproduction in a music CD Player is different from retrieval/usage method for non musical data applications which is what the CD writers/copiers use.

The Redbook specs for music CDs as written by Sony/Phillips some 30+ years ago retrieves data mostly sequentially in REAL-TIME since music is played in real time. The assumption was if there are errors on the disc/DataStream (missing data) it will be "filled" in by the error correction algorithm (ECA) which literally creates the missing data by "guessing" from the data that is ahead and behind the missing pieces. Since music is essentially analog waveforms, as long as you can "guess" reasonably close what that wave should look/sound like you can get away with this method. This was considered acceptable with music since music data is not mission critical (though this artificial creation of the missing data sounded bad).  This missing data and subsequent correction is happening ALL the time on ALL optical discs/drives but is generally acceptable for most people on most mid to low end systems. However when a large enough stream of missing data is encountered from bad scratches/manufacturing defects by the ECA it cannot recreate the missing data and therefore no music emanates from the player.
 
The Copy and Re-Write algorithms on the other hand were derived from the computing industry where DATA integrity is paramount. The computer cannot make up missing pieces of your Excel presentation by analyzing the existing data. So it was far more critical to retrieve and preserve every bit. Though bit errors do happen here as well and there are also error correction protocols here too, these are different. One of the differences is the Disc is slowed down and LASER is instructed to go back and forth and from different angles/focus until as much data as possible is retrieved from the flawed/scratched part of the disc.  Another is the data is then cached/buffered in much larger volumes before writing/copying. This can actually be seen by looking at the bit rate when copying discs. Bitrates will significantly drop on the bad parts of the discs when the laser attempts to read over and over again. (This interruption or slowdown of data is not crucial for your Excel Presentation but it would unlistenable for music application.)  Since the copy is made from these additional efforts which contain a lot less errors than the original, the copy is far more playable than the original. Because of this Audiophiles noticed years ago that a copy sounded better that the original which when first reported caused much controversy.

There are additional issues that make the copy sound better such as higher jitter/defects from aluminium optical discs, reflectivity index of the disc, the laser in a writer being superior than a player-only machine, etc, but outside of the scope of this discussion. This is also why certain high-end players that are designed with drives/lasers and programming to accurately retrieve maximum amount of data from the discs to store/cache/buffer them on either solid state or hard drives first, and then play the ripped data from the solid state/hard drive, sound significantly better than players directly streaming the data from the optical disc in real-time. (And why computer based streaming sounds so good.)

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