I'm a programmer and in programming a code can be bad or good. It is easy to see by the way the structure is built and how blocks of code are arranged, what functions and procedures are used, and how everything is organised.
In music as a composer I'm finding it hard to understand whether a score is notated well (whether it corresponds to a professional music notation style guide or rules of notation) or badly. This is probably because I'm not so good at sight-reading music myself, since I have little practice and haven't seen a lot of professional scores (I can't make a comparison to my scores). Anyway, I compose in Guitar Pro 7 (notate using this software) and I always ask myself, "Is the score I am notating good? Is it correctly done? Does is correspond to rules or style guides? Won't a sight-reader have problems playing the score?"
What makes a score well notated, let's say for piano for instance?
Edit: Someone might have misunderstood the question so I'll add what I mean by bad or good:
My point of view is that here the notes are improperly durated and tied to each other. The rests aren't optimised for readability. The key signature is missing, although we can see that the piece is written in a key with sharps or flats. The accidentals are a mess, which makes reading harder. Articulation is missing whereupon we can't say how the piece is to be played and what dynamics are used.
A lot of scores I find on the Internet are really badly notated in my opinion. I think this is a very problematic topic. i think that making the score look nice, easily readable and non-problematic for conductors or musicians is a very difficult task in fact.
Another Edit: Is it required to include dynamics and articulation in a score? Is it necessary to include fingering?