Why practices are not as important as principles?

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Why Practices are not as
important as Principles?
Simply... Complicated!
Tuesday, April 23, 13

Andrea Tomasini
Agile Coach & Trainer
andrea.tomasini@agile42.com
@tumma72
@agile42/coaches

principle |ˈprɪnsɪp(ə)l|
noun
1 a fundamental truth or proposition that serves as the
foundation for a system of belief or behavior or for a
chain of reasoning: the basic principles of justice.
• (usu. principles) a rule or belief governing one's
behavior: struggling to be true to their own principles | [ mass
noun ] : she resigned over a matter of principle.

practice |ˈpraktɪs|
noun [ mass noun ]
1 the actual application or use of an idea, belief, or
method, as opposed to theories relating to it: the
principles and practice of teaching
3 repeated exercise in or performance of an activity
or skill so as to acquire or maintain proﬁciency in it:
it must have taken a lot of practice to become so
ﬂuent.

Practices...

Daily Stand-up Meeting
A common practice used by many agile teams. In Scrum is
often used for the Daily Scrum

•Practice: the Daily Stand-Up meeting is about
meeting while standing. It’s a practice, often used by
Teams developing software following an Agile
approach. By standing the meeting will take less time,
and will be more focused, as standing for long it’s not
comfortable.

and now... you!
what did you do
yesterday?
Daily Standup Meeting
Control

•Principle: working in complex environment, with
rapid and not always predictable changes, and a lot of
dependencies, requires focusing constantly on the
goal to succeed. For this reason, it is important to
introduce regular check that allows a Team of peers
to re-asses regularly the status of progress and decide
how to move forward and improve

Planning Meeting
The moment in which Agile Teams decide what to do and
how to do it...

Planning Meeting
•Practice: The whole Team meets to agree on a goal
for the next iteration of work. During the meeting -
which is normally time-boxed - the Team decides
what will be transformed into working software, out
of a list of prepared items called Backlog, which
should reﬂect the order better suited to achieve the
goal.

Hey, that’s
enough Stop!
Planning Meeting
Shooting

Planning Meeting
•Principle: Agile Teams deliver working and
valuable software at regular interval. In order to
reduce the impact of changes on the development
plan, agile Teams plan in detail at regular interval of
time - normally between 1-4 weeks.
•Assumption: the length of the iteration is such that it is
acceptable for the Business to wait the next iteration to plan for
changes, so to reduce interruptions.

Pair-Programming
An eXtreme Programming practice to improve code quality
and design...

Pair Programming / Pairing
•Practice: all code to be sent into production is
created by two people working together at a single
computer. Pair programming increases software
quality without impacting time to deliver.

I need help, who
wants to pair?
Me! I’d like to
learn something
Pair Programming
for nothing
for free!

Pair Programming / Pairing
•Principle: It is counter intuitive, but 2 people
working at a single computer will add as much
functionality as two working separately except that it
will be much higher in quality. With increased quality
comes big savings later in the project.
•Note: One thing pair programming is not is mentoring. A
teacher-stundent relationship feels very different from two people
working together as equals even if one has signiﬁcantly more
experience.
http://www.extremeprogramming.org/rules/pair.html

Test Driven Development (TDD)
An eXtreme Programming practice to create simple and
effective design, by starting to write tests...

Test Driven Development
•Practice: is a software development process that
relies on the repetition of a very short development
cycle: first the developer writes an (initially failing)
automated test case that defines a desired
improvement or new function, then produces the
minimum amount of code to pass that test, and
finally refactors the new code to acceptable standards.

I am really eager
to try TDD on this
new design
Apparently this design is too
complicated for TDD... I don’t seem
to be able to write tests first.
Design
Testing

•Principle: In the spirit of simplicity - as the art of
maximizing the amount of work not done - agile
teams focus on implementing the minimal amount of
code needed to fulﬁlls the tests. In this respect the
design and the architecture will be emerging out of
the need of fulﬁlling those tests. By doing so the code
will remain simple, easier to maintain and evolve.

Continuous Integration (CI)
An eXtreme Programming practice to accelerate feedback
loop and learning...

Continuous Integration
•Practice: is the practice, in software engineering, of
merging all developer workspaces with a shared
mainline several times a day. It can be seen as an
intensiﬁcation of practices of periodic integration
advocated by earlier published methods of
incremental and iterative software development.

Dis-

•Principle: Agile teams are seeking constantly to
accelerate feedback loops, so to learn faster. In
particular teams value validated learning more than
assumptions based learning. Through discipline it is
possible to come to reproduce ready-to-ship software
as often as possible. In order to validate the learning
of having understood what needed to be done,
through stakeholders’ feedback.

Review Meeting
Agile Team meet regularly to review the status of their
Product evolution and decide what to deliver next...

Review Meeting
•Practice: The team and the Product Owner meet at
the end of every iteration and assess the results of
what was achieved. At the meeting may attend also
some of the stakeholder, so that they can provide
additional feedback.

Come on guys,
stay calm... believe
in what you did
Rejected! that’s
not what I want...
Product
Review
Compliance

Review Meeting
•Principle: through iterative and incremental
development of a product it is possible to learn what
is really needed and what not. By reviewing the status
of the product development regularly against the
currently planned value to deliver, the Team can
increase its effectiveness and learn what is really
needed to the stakeholders.

Understanding the Principles...

Pull principle
Iterative&
Incremental
Empirical Process Control
Lean Thinking
Agile Reading Glasses

Empirical Process control
Agile is based on empirical control, through transparency, inspection and
adaptation the best processes are emerging while doing, and only retrospectively it
is possible to recognize successful adaptation from non successful ones

Deﬁned Process Control Production-based process

Let’s make a test...
Complexity: the amount of agents in play
and their dependencies are so many that
it’s impossible to predict the state upfront
> 60!

Empirical Process Control R&D based process

Pull Principle
Agile approaches are based on pull principle which allows self-organizing teams to
pull in work and knowledge as needed in order to deliver valuable quality software

Push
Pull
Individual Team
Enforcement
Collaboration
C
om
pliance
Focusonvalue

Lean Thinking
Lean Thinking inspired process improvement through constant observation of the
unevenness in a ﬂow, resources or people overburdening and elimination of
wasteful activities

Overburden
(無理:muri)
do not overload your
People

Unnecessary
Variations
(斑: mura) keep the Flow
Even

Wasteful
Activities
(無駄: muda)
remove non value adding
Activities

Iterative & Incremental
Delivering a product in subsequent iterative releases, not only improves the explicit
quality of it, it also allows everybody involved in its development as well as every
stakeholder, to learn better what is really needed to support a business vision

Verify
Id
ea
Im
pro
ve
it
A
d
d
Value
R
ead
y
it
Done!
1 2 3 4 5
Iterative & Incremental
0% 100%

Every
Increment:
✓is inspect-able
✓adds value
✓it’s high qualityReady to
ship!

So what?

This old axe, is still
doing a pretty good
job after all...
Hey, you should try the new
Chainsaw, it’s much better
...is much heavier, and cuts no
way better than my old axe...
not all new things are better
after all...

What’s the recipe?
1) Focus on Value, not
compliance to rules!

2) Understand the Principles
and then learn the Practices

3) Assimilate the Principles by
Practicing more, and improve
the Practices by
conceptualizing better the
Principles

4) Build your own Practices,
as you learned to live the
Principles

Thank You!

More food for thought...
http://slideshare.net/tumma72
Now in
Croatian!

Why practices are not as important as principles?

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