Tarantino originally wrote the role of Butch for Matt Dillon. Instead of Butch, Dillon wanted to play Vincent. This posed a challenge for Tarantino, as Pulp Fiction’s green light hinged on the casting of one of Miramax’s approved actors that would draw audiences to the film. Dillon ultimately declined the role, and Tarantino was without a Butch. After a surprise meeting with Willis at actor Harvey Keitel's home, Willis was eventually cast in the role. Check out the whole saga as told by Tarantino himself:
Bruce Willis attempted to convince Quentin Tarantino to cast him as Vincent or Jules in Pulp Fiction before ultimately taking the role of Butch.