When an artist takes on their chosen medium, they don't know how long it will take to complete their art, for there is a process. It took Michelangelo four years to paint the Sistine Chapel and 16 years for Ernest Hemingway to write his masterpiece, The Old Man And The Sea. Led Zeppelin only took 30 hours to record their breakthrough album, Led Zeppelin I - great art knows no concept of time, and sometimes, neither does the artist.