Cricket has ups and downs and again ups. There was a time when for a long time West Indies ruled the game. From sixties and seventies, with giants like Garfield Sobers, Wesley Hall, Griffith, Alexander, Hunt, Holt right up to eighties and nineties with greats like Vivian Richards, Clive Lloyed, Andy Roberts, Richie Richardson, etc. Today they are in the dumps. Similarly India when Kapil Dev, Sunil Gawaskar Farookh Engineer, Bishen Singh Bedi, Prasanna, Chandrashekhar used to rule the game, and Pakistan too was on top in the days of Haneef Mohammad, Ejaz Butt, Fazal Mehmood, Imran Khan. Today are they just nothing. But the circle of cricket will once again bring these countries up and those who are up will go down. Who knows!
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It may be one of the reason but certainly not a valid reason. They become somewhat arrogant and that arrogant along with poor sportsman spirit and treating the other team as though they cannot play cricket before the match starts and also their media person also to be blamed. hence due to their overconfident , they started to loose match. One should have confident in yourself but overconfident , no it will not pay on a long run. Now, see where they are standing a near fourth position. the first three top places are S.A., Sri Lanka and India and their standing itself shows how they are . Moreover, they can revive and can be good provided they play squairely and fairly , then they can achieve the greatness.