Not necessarily. A string quartet can and will play many types of classical literature - not all pieces have four movements.
nuno flores string quartet or corvonuno string quartet
Oberlin String Quartet ended in 1959.
Atrium String Quartet was created in 2000.
Cypress String Quartet was created in 1996.
Goldner String Quartet was created in 1995.
Quartet = Four (4).
nuno flores string quartet or corvonuno string quartet
Miami String Quartet was created in 1988.
Lindsay String Quartet was created in 1966.
Lindsay String Quartet ended in 2005.
Oslo String Quartet was created in 1991.
Berkshire String Quartet was created in 1916.
Brentano String Quartet was created in 1992.
Dubois String Quartet was created in 1910.
Dubois String Quartet ended in 1938.
London String Quartet was created in 1908.
Conservatory String Quartet ended in 1946.