I am a good fan of Sri Lanka cricket from 1996 world cup. I am following world cup selection. It is becoming a culture or tradition that Sri Lanka are selecting 1/2 players in every world cup who are just adding numbers in squad.
In 2003, Avishka Gunawardene and Charitha Buddhika. As far as I can remember, Avishka got 1/2 game, but Charitha Buddhika didn't play any match. In 2007, Team was good. In 2011, Chamara Kapugedera not only entered in 15, but also added in 11. So, Sri Lanka played with 10 players in batting, 11 in fielding. Off course, Kapugedera is a very good fielder. In 2011, any one of Sanath Jayasuriya, Jewaan Mendis, Dinesh Chandimal could play instead of Kapugedera.
And now 2015, Dimuth Karunaratne and jewan mendis are just numbers in 15. Any on of Upul Tharanga, Kusal Perera can play instead of Dimuth Karunaratne and any one of Chaturanga de Silva, Sekugge Prassana, Ajantha mendis can play instead of Jewaan mendis. Both of these two players couldn't show any contribution in team.
So, my opinion, if there is any chance to change to squad Sri Lanka should take these issues seriously.