Many characteristics of a work can affect the application of fair use. Fair use of a commercial work meant for the educational market is generally disfavored. Courts more readily favor the fair use of nonfiction, rather than fiction. Commercial audiovisual works generally receive less fair use than do printed works. A consumable workbook will most certainly be subject to less fair use than would a printed social science text.
Amount is measured both quantitatively and qualitatively.
No exact measures of allowable quantity exist in the law. Quantity must be evaluated relative to the length of the entire original and in light of the amount needed to serve a proper objective. Motion pictures are also problematic, because even short clips may borrow the most extraordinary or creative elements. Motion pictures are also problematic, because even short clips may borrow the most extraordinary or creative elements. This concept is a qualitative measure that may weigh against fair use.