I know why they got it. It's because they are a beneficent team. The ICC wants to play God and reward them for their act of kindness. You really have to believe me. I have evidence:
1) NZ allowed SL to score only 216 runs in the first ODI, India let them score 307. But they do get demerit points for not letting Sanath score his century. He was bitten on the leg by some strange Penguin-like creature. Shame on you Nehra. When you give, give everything. You will spend one day in cricket hell.
2) They dropped catches and misfielded several times. This is clearly an act of giving, sharing and caring. If they had held all their catches the ball would feel suffocated in their hands and ultimately die. If they had not misfielded, the ball would not have been able to run free into the ropes. Restriction of freedom is a very serious offence you know. Particularly in the ball world.
3) On an average, each bowler gave over 6 runs per over. They felt that SL will surely return their generosity when it came time for them to bowl.
4) But India could not stop giving. So they kept on giving their wickets. Particularly to Angelo Mathews. They thought from his name that he was a real angel and would guide them to a place where they can continue to bat after Tendulkar and Dravid fall. That didn't happen..and it never will.
How can such a benevolent team not get the number one status? I would like to thank the ICC for coming up with such a ranking system. It truly is the greatest thing on Earth.