Why does it change?
Software changes does not change primarily because it doesn’t work right
- Maintenance in software is different than maintenance for automobiles
But rather because the technological, economic, and societal environment in which it is embedded changes
This provides a feedback loop to the software
- The software is usually the most malleable link in the chain, hence it tends to change
- Counterexample: Space shuttle astronauts have thousands of extra responsibilities because it’s safer than changing code