Art is a matter of opinion..
The ability to shade appropriately (when necessary) can make an artist good, but it also dependent on other factors such as creativity, quality of art, colours and effort.
Shading is an important skill to learn and as such it can make a good artist better, but sometimes no shading is needed either
I quite like this head, it looks like an Indian or aboriginal style art. The sides are a bit empty and I don't particularly like the mouth, but it is a unique head. The edges seem blunt, they might look better with sharp edges