Software laws Flashcards
1
Q
What is the most expensive part in software life?
A
90% of costs is on maintenance/evolution.
2
Q
Lehman’s first law
A
(law of continuous change)
A program used in a real-world environment (e-type) mus change or become progressively less useful in that environment.
3
Q
Examples of studies to confirm Lehman’s laws
A
- IBM OS360 operating system
2. Linux
4
Q
Lehman’s second law
A
(law of increasing complexity)
As an evolving system changes over time, its structure tends to become more complex or degraded and extra resources must be devoted to preserving and simplifying its tructure
5
Q
User involvement in software evolution
A
If software isn’t used it’s not evolving (SourceForge experience)
