How did the covid-19 outbreak in India get so bad?

Another variant, B. 1.617, has become the dominant variant in the state of Maharashtra, according to Nature. That variant is sometimes referred to as the “double mutant” variant because it contains two key mutations that were found in two other highly infectious strains. So far, however, there is no hard data that suggests that B. 1.617 is more transmissible than other variants, and India does not perform enough genome sequencing to determine whether B. 1.617 is driving the current outbreak.

Source: WP