A response to a complaint

Someone blogged this complaint the other day and I thought it would be good to address this:

Ok here's the question for all you students of political economy. Which of the following two statements is most accurate.

1. It is important for people to get regular eye exams and therefore prescriptions should expire after a time. Without this requirement, people would wear prescriptions too long and would jeopardize public safety and their own health.

2. The Optometrists lobby wants more business for its clients and knows that requiring current prescriptions will increase the incomes of opticians.

Here's my response:
I think the reason for regular eye exams is more medical than optical. There are medical problems that can occur from wearing a prescription past its time. For instance, eye strain, excess convergence etc. There is a risk too when a prescription changes slowly. Someone may not be legal to drive and say "my glasses are fine." I've seen it. Still, more than just the spectacles it is important to be checked for medical problems on a regular basis. Glaucoma, diabetic retinopathy and others can occur without any symptoms and may lead to blindness if not diagnoses in a timely manner. Clear View Eye Care believes in doing yearly eye exams to prevent these medical conditions regardless of how well the glasses are performing.