What is the word for someone who jumps from one artistic media to another but they never master anything. I remember a professor using it once and I just can't figure it out. (For example, Rob tried painting for 2 years, now he's into photography, but wait, he just started writing.) At the end of it all, he just dabbled here and there but isn't mastering any of them. I know the word has a a negative connotation. I'm not even sure if it even has to be an artistic related word, I just remember my art professor using it with that example.
Could the word have been dilettante? It doesn't necessarily imply several different media, but it means a person whose interest in (usually the arts) is only superficial.
"Jack of all trades, master of none" is a figure of speech used in reference to a person who has dabbled in many skills, rather than gaining expertise by focusing on one.
. . . When abbreviated as simply "jack of all trades", it is an ambiguous statement; the user's intention is then dependent on context. However when "master of none" is added this is unflattering and sometimes added in jest.