The document discusses different perspectives on defining and measuring software quality. It presents Gerald Weinberg's definition of quality as "value to some person" and discusses quality in terms of usefulness, correctness, and goodness. It outlines eight perspectives of quality - from the customer, business, team, and company standpoint - spanning ideas, implementation, and support of a software solution. The document also notes that quality is subjective but can be measured through collaboration, consensus building, and key indicators like processes, bugs, releases, and customer feedback.
4. Quality is value to some person
- Gerald Weinberg
Quality Software Management: Volume 1, Systems Thinking, 1992
“ ”
The Definition of “Quality”?
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5. Quality is value to some person
- Gerald Weinberg
Quality Software Management: Volume 1, Systems Thinking, 1992
“ ”
The Definition of “Quality”?
@DanAshby04 5
6. Quality is value to some person
- Gerald Weinberg
Quality Software Management: Volume 1, Systems Thinking, 1992
“ ”
The Definition of “Quality”?
Conformance, Correctness, Works, Fitness, Purpose…
Excellence, Fineness, goodness…
Value, perspective…
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11. The quality of our
observability, monitoring,
release processes, pipelines
8 Perspectives of Quality in Software
Activities relating to the
ideas of a solution
Activities relating to the
implementation of a solution
Activities & services
relating to the live software
The quality of customer
support feedback
opportunities & mechanisms
The quality of our
implementation regarding
code, arch., designs, etc
The quality of our ideation
regarding business value:
growth, conv, usage, etc
The quality of the
experience of using the
implemented software
The quality of our ideation
regarding customers and
users wants & needs
The quality of the team, their abilities, attributes and maturity relating to their
processes, knowledge, skills, communication and collaboration styles and
methods, ways of working, tooling, etc
The quality of the company regarding it’s culture, leadership, the values and
principles, org structure and strategy, learning mechanisms and support,
communities, leadership support, recruitment, diversity, etc
External Quality
(from customer perspective)
Internal Quality
(from business & team perspective)
Team Quality
(feeds internal & external quality)
Company Quality
(feeds team’s processes & morale)
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13. 8 Perspectives of Quality in Software
Activities relating to the
ideas of a solution
Activities relating to the
implementation of a solution
Activities & services
relating to the live software
External Quality
(from customer perspective)
PROACTIVE Quality REACTIVE Quality
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Internal Quality
(from business & team perspective)
The quality of our
observability, monitoring,
release processes, pipelines
The quality of customer
support feedback
opportunities & mechanisms
The quality of our
implementation regarding
code, arch., designs, etc
The quality of our ideation
regarding business value:
growth, conv, usage, etc
The quality of the
experience of using the
implemented software
The quality of our ideation
regarding customers and
users value: wants & needs
The quality of the team, their abilities, attributes and maturity relating to their
processes, knowledge, skills, communication and collaboration styles and
methods, ways of working, tooling, etc
The quality of the company regarding it’s culture, leadership, the values and
principles, org structure and strategy, learning mechanisms and support,
communities, leadership support, recruitment, diversity, etc
Team Quality
(feeds internal & external quality)
Company Quality
(feeds team’s processes & morale)
15. The quality of our
observability, monitoring,
release processes, pipelines
The quality of customer
support feedback
opportunities & mechanisms
The quality of our
implementation regarding
code, arch., designs, etc
The quality of our ideation
regarding business value:
growth, conv, usage, etc
The quality of the
experience of using the
implemented software
The quality of our ideation
regarding customers and
users value: wants & needs
The quality of the team, their abilities, attributes and maturity relating to their
processes, knowledge, skills, communication and collaboration styles and
methods, ways of working, tooling, etc
The quality of the company regarding it’s culture, leadership, the values and
principles, org structure and strategy, learning mechanisms and support,
communities, leadership support, recruitment, diversity, etc
Team Quality
(feeds internal & external quality)
Company Quality
(feeds team’s processes & morale)
Testing Activities Relating to the 8 Perspectives
Activities relating to the
ideas of a solution
Activities relating to the
implementation of a solution
Activities & services
relating to the live software
External Quality
(from customer perspective)
Customer interviews,
exploratory testing the ideas,
risks analysis and mapping, etc
Exploring designs and operational
SW, automated checks,
investigating assumptions, etc
Exploring IM and CS processes,
checking our feedback
mechanisms, etc
AB Experimentation, exploring
our business metrics, etc
Code reviews, exploring the
architecture, exploring
integrations, etc
Exploring observability solutions
and tooling, exploring release
pipeline processes, etc
Exploratory testing our processes, ways of working, ways of measuring and reporting, our communication
methods and our decision making processes, etc
Exploratory testing our company values and principles, the org structure and org strategies, exploring our
morale, exploring our ways of learning and our leadership support mechanisms, etc
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Internal Quality
(from business & team perspective)
20. It’s Subjective
It’s Relative
It’s Personal
but… Subjectivity + Comms & Collab = Intersubjectivity
Can You Measure Quality?
(Intersubjectivity = shared opinions through consensus; or from a social science perspective, it’s “agreement”)
https://en.wikipedia.org/wiki/Blind_men_and_an_elephant
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21. Collaboration + Consensus = One Possible Solution
Images created by Jeff Patton (from his book: “User Story Mapping”)
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22. Some ideas on showing a measure of quality
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23. Very high
High
Medium
Low
Very Low
None
Unknown
Extreme Major Moderate Minor Very Low
a Consensus of Confidence in QualityMeasuring
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Confidenceinquality
(throughconsensus)
Perception of complexity
(through consensus)
Feature A
Feature E
Feature D
Feature C
Feature B
Feature F
24. A dashboard of leading & trailing quality indicators
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Process Adoption
(Leading Indicators)
Prod Bugs Quality Indicators
(Trailing Indicators)
Engineering / Release Quality
Indicators (Trailing Indicators)
Business Metrics
(Trailing Indicators)
Customer Verbatims
(Trailing Indicators)
Processes Perception
Risk Mapping…………………………………..
Test Driven Development………………
Behaviour Driven Development…..
Domain Driven Design……………………
Deep Work Sessions……………………….
Session Based Test Mgmt……………….
Rolling Wave Planning……………………
Tech Debt Payback Plan……………….
Quality Debt Payback Plan…………..
CI/CD Pipe Improvements………………
Roadmap Maintenance…………………
Story Mapping………………………………...
Example Mapping……………………….....
P&L Churn 35%
Conversion +5%
User Growth +3%
User Traffic 150K
“I like the new desktop browser view”
“You shouldn’t have gotten rid of this
feature…”
“Here’s an idea – I would really like this”
“This is so unusable. It’s causing me so
much despair! ”
Open Prod Bugs:
Prod Bugs
last week:
OOSLA:
Severities:
9 2
1 1 3 5
Sev1 Sev2 Sev3
Number of releases
last week:
DoD Adherence:
Release success:
Rollbacks:
15 68%
100% 5
26. Recap & Final Thoughts
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• Quality consists of “correctness”, “goodness” and “usefulness”.
• The 8 perspectives model helps to visualise the differences across customers,
business, teams’ abilities and the company – spanning across the ideas of the
software solution, the implementation of the solution, and the services supporting
that solution too.
• Quality is subjective, but intersubjectivity helps build a consensus perception of
quality.
27. Thank you!
Dan Ashby | @DanAshby04 | DanAshby.co.uk
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