I recently had a conversation with a fellow cyclist on wearing glasses while cycling and it made me realize that many cyclists do not understand the importance of this safety accessory. I think the only way of explaining why shatterproof glasses are important is by sharing my story and how I almost lost an eye.
I was mountain biking in 2011 along a trail I had ridden many times. I was on my final descent of the day and suddenly flew over my handlebars. My next memory was waking up in the dirt trying to understand where I was and what had just happened. When I arrived at the hospital, the doctors told me I had lost consciousness, cracked my helmet in half and had a severe concussion. They also told me I would have severely damaged my right eye (might have even lost it) had I not been wearing my shatterproof glasses and cracked my skull open had I not been wearing my helmet. My glasses were completely destroyed but did not shatter and prevented me from losing my eye. My helmet cracked in half but my head did not.
So, buy some shatterproof glasses, a good helmet, wear them, love them.