I fully agree with Austin, so won't cover the same ground.

However, there has been a recent development in 'remastering', which is not to literally remaster the best surviving copy of the original mix [of which there will likely be several, compressed &/or EQ'd for different original purposes - for cutting to vinyl, cassette, etc].

Instead, record companies are going back to the original analogue multi-tracks & cleaning up from that point; then re-creating a close approximation of the original mix, but with modern 'sensibilities' & criteria.

The intention of these remakes is not to alienate the original listener, but to encompass newer listeners for whom the original small bandwidth, poorly compressed, scratchy version would not convince them at all, no matter how well it was cleaned up. There is definitely a limit to what you can do from a mono or even stereo original master, compared to what you can achieve by going to the multitracks & starting over.

This can be somewhat contentious, of course, but the idea is that you do the remix/master to the best possible modern standards without doing anything silly like putting gated reverb on a 1972 snare [case in point, the late 80s 'remasters' of Free's Greatest Hits, complete with hideous added digital reverb on the snare.]

I'll see if I can get permission to post some small educational examples & add to this post.

Edit I got permission to post this tiny snippet to Soundcloud - as the track is already known to have 'escaped', unfortunately.

These are not the full-quality finalised versions of either the original or remaster, but are of just sufficient quality to hear the difference.

https://soundcloud.com/graham-lee-15/super-snippet