We often take the most basic things we enjoy for granted. We are able to enjoy improved vision through wearing glasses today because of the innovation of others throughout history. Some of the first spectacles were simply glass magnifiers that were held by hand.
While glass was once used to manufacture lenses and metal was mostly used for frames, materials that are lighter, more versatile and easier to work with now mean that the glasses manufacturing process is now faster, cheaper and can be automated. Bone, ivory, leather and even tortoise shells were once commonly used to make frames to house lenses.
While the glasses manufacturing process may need human hands at specific points, much more of it is now automated, meaning your glasses can be manufactured and sent to you a lot faster.