Consider the pervasive Compact Disc Jewel Case. It is a terrible design: extremely fragile and prone to breakage. Never drop a CD. Somehow, these things are the most successful design, despite uncorrected design errors including:
- The hinges are extremely easy to break.
- The teeth that hold the inside of the disc break easily
- The front and back faces crack easily if pressure is placed on them
- Front booklets are difficult to get out
- Front booklets can be easily be replaced incorrectly, warping or tearing the paper
The thin dual-disk design Jewel cases are even more fragile. Some disks come in a sleeved cardboard "jewel case"; some of these are susceptible to scratching. The best designed case I have seen has a cardboard outer and a glued-plastic disk tray with hardened disk teeth. It resists all five design defects noted above.