Well, the appendix is a good example of the conservative nature of evolutionary change. There are more than a few genetic traits that have no evolutionary advantage and yet still persist, like attached earlobes or the ability to roll your tongue.
1. repulsive or distasteful.
2. excessively sweet or sentimental.
3. unsophisticated or old-fashioned.
4. sticky; viscid.
(According to dictionary.com)
To the systems programmer, users and applications serve only to provide a test load.