What if a situation arises when say Group team with 0.188 net runrate is 3rd best in the group and another team of different group has 0.187 net runrate and is second in the group. Both the mentioned teams has equal points.
Ideally, the first team has better NRR and should proceed to semi-finals but thanks to the group thing, despite having better NRR, the first team will not qualify while the second team of other group with lesser NRR will qualify for semis!
Groups has its own debatable drawbacks, my friend.