We all understand the concept of what they are trying to accomplish and even if you absolutely believe that is the right social strategy, this is not "driven by science" as the goals, hurdles, percentages, etc. are not from a scientific, mathematical model, they are completely arbitrary criteria to help achieve their desired goal.
Just like the various hurdle numbers that make up "Purple", "Red", etc. are not "science" they are milestones that are arbitrary and directional. That is why every state in the country has different "science" and the UK, US, France, etc. all have different "science".