Can vision ever be 100% perfect with glasses?

Question

How often does vison change?

Can someone where the same glasses for 10 years w/out there vision changing?

Answer 1

It can be close but not 100%. It is possible however to wear the same RX for 10 years or so without a change, but generally anyone should get checked every couple of years. Anyway, as a person gets older the lens within your eyes looses the ability to focus on whatever you are looking at. As a child these lenses are pliable and can focus easily but as one gets older they loose this property. This is why someone 30+ years old may need bifocals or trifocals. These compensate for your eyes ability to focus.

Answer 2

The aim of any exam is exactly to tune the eye with glasses to 100% of the vision it is capable of.

Occasionally rigid contact lense can deliver better vision than any spectacle Rx can, but more often spectacles can supply better vision than can be obtained with soft contact lenses.
(The soft contacts have *other* advantages, so they are often chosen despite this)

How often the Rx changes is very variable.
With children and teenagers change is more the rule than the exception, but it's not rare for an adult to go ten years with no significant change in their distance Rx.
The increasing need for a reading Rx past 40 or 45, however, is pretty much a given.
(with a few exceptions for unusual refractive conditions)