There are many factors that outline the decline of Sri Lankan cricket. The two main ones are:
1. War"The civil war in the 2000's affected the talent pool since most of the youth were forced to got to war or flee.
2. End of the golden generation: During the late 90's, Sri Lanka experienced their first "golden generation" of Cricket with talented players such as Kumar Sangakarra,Arjuna Ranatunga, Aravinda De Silva, Sanath Jayasuriya, Marvan Atapattu, Chaminda Vass, Muttiah Muralitharan, Mahela Jayawardene,etc emeraged and catapulted Sri Lanka into a dominant cricket side.