Agility, Business Value and the 11 Axis Of Software Quality

ACCU 2009© Schalk W. Cronjé

Agility, Business Value &

the 11 Axis of Software Quality

Schalk W. Cronjé[email protected]

mailto:[email protected]


Are you still agile?

Do you believe in quality?

Do you deliver business value?


Agility, Business Value & the 11 Axis of Software Quality● Agility and institutional theory● Views of quality● Software quality factors● Measuring for value● The real world


Human capital

● Knowledge● The most important asset of any organisation● Hated by bean counters

– Difficult to measure● Requires non-linear, empirical management


Institutions● Sets of internalised rules

supported by values– Has tacit influence– Rules will be contested

● Shape understanding of social meaning + order– Provides a framework for

performance● Shapes of rights + duties

– Political authority– Economic opportunities

Institution

Organisations

People

An organisation can become "institutionalised"Institutions don't last forever


Scott's Model

Societal Institutions

Organisational Fields

Organisations

Actors(groups/individuals)

diffuse, impose

diffuse, impose

diffuse, impose

invent,negotiate

interpretinnovateerrorinvent,

negotiate

Limitations of cognitive / social rationalitySelective perception

sanctionbehaviour

invent,negotiate


Agile Today

● Mature● Well-known methodologies● Embraced by many

– Even if only by lip service● Misunderstood by many● Too easy to tick the boxes

than to deliver value● Tyranny of the urgent

– Discipline

agiletoday


Time to Revisit Agile Values

We value people and interactions above processes and tools

We value responding to change over following a plan


Business Value

● "Business Value" is executing / procuring / producing that which is of "value to the business"

● Responding to change can provide value● Indirect actions at grass roots can provide

long-term business value


Quality as an Institution

● Well known concept● Contested nature● Has a tacit influence● Embodied in many organisations● Cannot be directly measured● Improving quality can have side-effects


Product / Service Quality Features (Kano model)

● Primary– Basic features

● Secondary– Distinguishing performance features

● Tertiary– Excitement features– Discovered after purchase– Predisposes to repeat purchase

Quality scope == Fitness of Use


Cost of Quality

● Appraisal costs– Discovering condition of hardware & 3rd-party

software components● Internal failure costs

– Defects found before shipment● External failure costs

– Defects found after shipment● Prevention costs

– Costs for preventing all of the above


Correctness

The one always remembered

Relative easy to quantify

To what extent does the system satisfy requirements

and meet objectives?


Reliability

Directly related to fitness of

use

Measures of stability and precision

Know your boundaries


Usability

Effort to learn and use the application / API

Difficult to measure

Builds perception


Maintainability

Effort required to find, fix and test defects or update running

systems

Affects process throughput

Major long-term costs


Portability

Effort to adapt to another HW /OS / SW environment

Separation of concerns

Requires vision


Efficiency

Resource usage

Directly related to fitness of

use

Know your boundaries


Testability

How easy is it to test the system?

Design it inTime and cost

contributor


Flexibility

Effort to modify / adapt to different consumers

... know your boundaries

Are you responsive to change? but...


Integrity

Access control

Design in, rather than

afterthought

Cost of violation can be

high


Reusability

Repackaging within other applications

Reducing cost of others

APIs / SOA


Interoperability

Effort required to connect systems together

Cost for others to connect to your systems

Use of standards


11 Axis of Software Quality

ReliabilityCorrectness

Usability

MaintainabilityEfficiency

Testability

Flexibility

IntegrityInteroperability

ReusabilityPortability


Agility, Business Value & Quality

● Quality contributes to business value● The team is in the best position to judge

software quality● Quality is a tacit process

– Need ways to frame quality

It's business value Jim, but not as you know it


"Value delivery advocates measuring value using quantified business objectives in

alignment"

Ryan Shriver, Overload 89, Feb 2009


Strategy

AdvocacyEvaluation

Why measure?


Measuring for Value● Metrics are nothing, measuring is everything● Start small● Think strategically● Apply Pareto's law● Use checks and balances● Avoid too many metrics● Know when to change reason to measure

– evaluation → advocacy● Know when to no longer measure


Example: Clean Build Failures

● Measures of daily clean-room failures– Tracked over quarter– Daily visibility

● Very simple measure - small heartbeat● "Getting in the groove" metric

– Subtle team introduction to measurements– Team can relate to objective


Example: Code-coverage

● Code coverage measures amount of code exercised during a test run.

● Code coverage does not:– validate usefulness of tests– directly address any of the software quality factors

● Why measure it?– Implies underlying automated tests– Change in coverage implies change in quality


Example: Outage Time

● Measure the time production systems are off-line

● Uses Nagios statistics● Addresses reliability


Metrics vs Business Value

● Do these metrics contribute to business value?– Clean-room failures– Code coverage– Outage time


How do you measure up?

ReliabilityCorrectness

Usability

MaintainabilityEfficiency

Testability

Flexibility

IntegrityInteroperability

ReusabilityPortability


"Excellent system qualities are a continuous management and engineering

challenge, with no perfect solutions"

Tom Gilb, Overload 85, June 2008


Institutional Sustainability

● Continual maintenance● Human capital development● Mutual trust building

– Historical perceptions● Requires learning

– Environment that "learns to learn"● Humans create quality not technology● Tied to continuous improvement


End note

If change does not make sense, it will not happen.

Agility, Business Value and the 11 Axis Of Software Quality

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