Eye tests for drivers of all ages should be something that we do regularly and voluntarily, but it is likely that there are many drivers on the road today whose eyesight is not up to standard. Mandatory testing would likely see these drivers have their licences taken away and make the roads safer for everyone else. Testing reaction times would also have the same effect. Given that mandatory testing such as this would probably need to be paid for by the drivers themselves, it seems like this could generate funds for the government, but perhaps not as much as keeping as many drivers as possible on the road.