Players tend to judge how "good" a performer is by how much they sound like the original recording. I think this is less important to the audience than most players realize but that is another subject. In most aspects of life however we need to have a basis for judging an end product. That's all well and good when we're forming a judgement about, say, a steak we order in a restaurant but it is totally unrealistic and possibly unfair when it comes to art.
About twenty-five years ago I happened to catch a trio at a local bar who (in my view, at the time) were just amazing because they could cover songs by groups like the Doobie Brothers and the Beach Boys with uncanny accuracy. Their three-part harmony was spot-on and their playing was many cuts above what I normally heard at bars. Kathy and I, along with some friends became devoted followers of the band and we couldn't wait to hear them play those covers, again and again. All three members of the group were Berklee guys, which is neither here nor there - I know now - but at the time I attributed their great playing at least in part to their schooling.
As luck would have it, when they broke up I began playing with one of the members who was a great guitarist and keyboard player with a tenor voice that could accurately reproduce just about any pop singer. I thought he was great but sadly, he had a very cynical view of the music and in fact of performing in general. I only gigged with him for a few months and it took me many years to figure out why he was so cynical and almost bitter about playing covers. I think he felt compelled to parrot back the music - because he could! My guess is that he would much rather have been doing his own versions of the songs but for whatever reason he felt that was not an option. His reaction to this was to paste a Cheshire Cat smile on his face when people would ooh and ahh about his performances and afterward mock them for thinking it was so great. Very sad.
Fortunately most of us won't end up in that place. We will struggle to come as close as we can to what we hear on a recording, and this is a good thing - up to a point. You can learn much from deciphering what a recording artist does but you should view that information as more money in the bank of creativity. Never be afraid to add your own elements to the piece of music. This will inevitably lead to a greater sense of satisfaction and open the door to even more advances in your playing.
Peace & good music,