Kitsch is used for describing works that are tasteless copies of an extant style or worthless imitations of valued art. Kitsch art is usually pretty tacky and, though appeals to popular taste, has a very poor quality. Kitsch also refers to aesthetically inadequate art; and art that is unable to make creative gestures other than the imitation of the superficial appereances of art (which can be made possible through repetition of convention and formulae).
This word started to get more popular in 20th century. The deliberate use of cultural icons as a very rich market caused an output of a variety of mass-produced and therefore cheap, unoriginial, sentimental, weak and ugly looking objects (like Mona Lisa scarves or any other masterpiece that has been used in a very riddiculus content). Kitsch art yields to popular demand alone and is created only for commercial purposes; which is very contradictory with the concept of self-expression by an artist.
There is a museum for kitsch art in Stuttgart.