Here are a few thoughts on the difference. Think of a piano player. If the player is not very good the music that he plays will not have much value, but if he has been practicing for years and is extremely professional, then the music will be a very valuable. Also, where many inexperienced artists get confused on this question (in my opinion) is when they rely on concepts . For example a happy-face is a concept. It is a symbol and a concept of a happy person, it is not “art”. Or for example, when an artist puts words on a painting, these are concepts. Another problem is decor is not art! Decor is something that matches the curtains, but does not rise to the level of Art.
Be sure to order the ART book for more on this subject.
There is a thin line between Fine Art and Decor. These are a few of my ideas. Feel free to add any thoughts you have on the matter.