An interesting, scientific study published by Stanford University suggests that using examples (i.e. copy prior work) early on in the creative design process improves the creativity of the output. The emphasis here is on, early in the process. Using prototypes and repeated look at examples improved the output even further. However, using examples also increased the conformity of the output.
Also interesting considering the outcome of the Apple vs. Samsung case.
Creative Process: Early use of examples improves output