Why is having a small PD won't work on big/wide glasses?

[Naomi Eyeglasses]

I needed to know, Why is having a small PD won't work on big/wide glasses? I want to get those pair, but said it won't work on me. I have a small face.

[Harley Eyeglasses]

The last pair of prescription eyeglasses I purchased cost nearly $600 and didn’t fit my face. I knew as I impulsively selected the fashionable little frames that they weren’t going to work, but I grimly went ahead and allowed the sales person to write up the order. A couple of days later, I picked up my glasses and took them home, where I wore them unsuccessfully for about two hours. Then I put them into a drawer, never to be worn again. Later, the store called to ask how my glasses were working out. I admitted that I had made a huge mistake, that the glasses didn’t fit my giant head, that I couldn’t see out of the lenses because they were too small and the glasses kept sliding down my puny nose, and that I was relatively miserable about having spent that kind of money on something that I couldn’t use.