It depends.

• Sometimes it’s because of structural Anglocentrism making it harder to get an acting role with a foreign-sounding last name (e.g. “Ramon Antonio Gerard Estevez” becomes “Martin Sheen” or “Ilyena Lydia Vadilievna Mironov” becomes “[Dame] Helen Mirren”)

• Sometimes it’s just a matter of cropping a name or two (“Philip Anthony Hopkins”)

• Sometimes it’s just about sounding cooler (“Eric Bishop” becomes “Jamie Foxx” or “Caryn Elaine Johnson” becomes “Whoopi Goldberg”)

• And sometimes it’s because there’s already a SAG member with your name (“Diane Hall” becomes “Diane Keaton” or “Michael Douglas” becomes… “Michael Keaton”)