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:

  1. The hinges are extremely easy to break.
  2. The teeth that hold the inside of the disc break easily
  3. The front and back faces crack easily if pressure is placed on them
  4. Front booklets are difficult to get out
  5. 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.