The difference in quality

I am preparing for a sunglasses sale on April 18th. I have been increasing my stock of sunglasses so I have a good selection to sell. I have a number of frames from Kate Spade to Elizabeth Arden to a discount frame called DG. One thing I noticed was the stark difference in quality between the "name" brands and the low cost brand. The plastic felt different, the way the frames were colored was different, the hinges were different. There is definitely a difference when it comes to quality sunglasses.