1.2.3 Errors, Defects, and Root Causes

Question 1

Humans make “ “ which produce “ “ which in turn may result in “ “.

Answer 1

errors (mistakes)

defects (faults, bugs)

failures

Question 2

Humans make errors for various reasons:
- time …
- work …
- pro…
- instra…
- simply …
- lack a…

Answer 2

• time pressure
• work product complexity
• processes
• infrastructure or interactions
• simply tired
• lack adequate training

Question 3

Defects can be found in:
- documentation, like …
- in s…
- in a supporting …

Answer 3

• documentations, like in requirements specifications or a test script
• in source code
• in a supporting work product like a build file

Question 4

Defects in work products produced … often lead to…

Answer 4

earlier in the SDLC, if undetected,

defective work products later in the lifecycle.

Question 5

If a defect in code is executed, the system may …

Answer 5

fail to do what it should do, or do something it shouldn’t, causing a failure.

Question 6

Failures can also be caused by

Answer 6

environmental conditions like when radiation or electromagnetic fields cause firmware defects.

Question 7

A root cause is a fundamental…

Answer 7

reason for a problem occurrence (a situation that leads to an error).

Question 8

Root causes are identified through

Answer 8

root cause analysis, typically performed when a failure occurs or a defect is identified.

Question 9

By addressing the root cause, it is believed that further similar …

Answer 9

failures or defects can be prevented or their frequencies reduced.