Shortly the Mars rover Curiosity will be receiving what some are calling a ‘brain transplant’. Now that the rover is on the surface, its software will be updated to give Curiosity the ability to drive and use a sampling system. Think of it as clearing out apps no longer needed and adding programs required by new surroundings.
Why was this necessary? While it’s certainly true that software is often updated in the eight months it took Curiosity to get from Earth to Mars, storage capacity was not the foremost desired feature of the rover’s computer – durability is. So while Curiosity’s processor can’t run as fast as your phone (or store as much), it’s certainly better able to land on a nearby planet after a long trip exposed to the rigors of space.
Tradeoffs matter. The same can be said for policies. Those seeking some kind of “evidence-based policies” may need to be reminded – often – that an evidence base is never the only desired feature of a policy.