i understand. well what i already mention is basic idea on mastering. you can check out some youtube vids of Greg Calbi cause he explains it really well for anyone to understand basically. also once you know or have a basic idea you will then start pick it up easily with every track you make or listen to. also as a hint when looking for well mastered music it's usually the vinyl copies that are better mastered and not tampered with cause they know the crowd that listens to vinyl. usually the cd and digital version gets boosted and dynamics get cut. that's why lot will still tell you vinyl sounds better cause it still has the music's dynamics intact.
My understanding of why vinyl are better mastered has more to do with the limits of vinyl than anything else. Probably something to do with the s/n of vinyl compared to the CD. As well as how close can the grooves be placed and all that other stuff.