As we age the lenses of our eyes naturally become less flexible. That makes it harder to focus on things up close, which is why most people over 50 will need reading glasses.
So basically spoiled people like me realize at 40 what a pain glasses are. I have a new respect for people that have had to wear glasses all their lives.
$80 for a 2.5mL bottle of pilocarpine that's 0.25% stronger than the 1% pilo which would cost $25 for a 15mL bottle. AND a risk for a retinal detachment.