This document discusses the differences between incremental and iterative development processes. It explains that incremental development delivers completed features one piece at a time, while iterative development refines incomplete features through multiple iterations. Both can be used together in an iterative and incremental process where development occurs through partial deliveries that add new features or refine existing ones. Managing requirements and uncertainty are also different with each approach.

1. Iterativo e incrementale
La spiegazione che hai sempre sognato (e mai ottenuto)
Marco Massarotto, Ph.D.
Agile Coach (CSP-SM®)
@MassaMarco
MassaMa
Modena

2. Passionate about PERSONAL and ORGANIZATIONAL development.
Committed to continuous improvement,
mixing together TECH expertise and HUMAN values.
Marco Massarotto, Ph.D.
Agile Coach (CSP-SM®)
Good Kaizen starts right within oneself!
• 10+ years with Agile, especially Scrum.
• Background as: COO (Improvement
Champion), Product Owner (PO),
Project Manager and web developer.
Love exploring about the “human factor”… Life coaching (trained Co-Active
Coach®), personal grow (P.R.H.), Mindfulness (MBSR) and Yoga.
@MassaMarco
MassaMa

3. Why this talk
<< We CONJOIN ITERATION and INCREMENTING.
In Agile development we actually conjoin these two tactics.
During a development “iteration” where we build several
user stories some may be adding new functionality
incrementally, others may be iterating to improve, change,
or remove existing functionality. >>
Jeff Patton

4. Why this talk
<< Incremental development is distinctly different from
iterative development in its purpose and also from its
management implications.
Teams get into trouble by doing one and not the
other, or by trying to manage them the same way. >>
Dr. Alistair Cockburn

5. Within (mostly) agile minds
Incremental process
Iterative process
Jeff Patton
Iterative & Incremental process

6. Requirements and process
Incremental
process
Iterative
process
ProcessRequirements

7. Requirements
Case 1:
Tentative idea
Case 3:
Fully formed idea
Case 2:
Seemingly formed idea
• Scope starts out quite
vague and is better stated
over time.
• Scope starts partially vague
and partially detailed.
• Scope is completely known
from the beginning.
Uncertainty

8. Two dimensions
Incremental process
Iterative process

9. Two dimensions
Scope ↔ Completion ↕
Full ●
Partial ○Partial ○
Full ●
Partial ○ Full ●
Scope ↔
Completion ↕

10. Waterfall development (traditional)
Nothing
Value
Time
• Full scope - full completion
delivery
• From nothing to everything
Partial ○ Full ●
Scope ↔ X
Completion ↕ X
All
Uncertainty

11. Incremental development
Time
Partial ○ Full ●
Scope ↔ X
Completion ↕ X
• Partial scope – full completion
delivery
• Progressive addition of complete
parts
Nothing
All
Value
Uncertainty

12. Iterative development
Nothing
All
Time
Partial ○ Full ●
Scope ↔ X
Completion ↕ X
• Full scope - partial completion
delivery
• Progressive refinement of
everything
Value
Uncertainty

13. Incremental & iterative development
Value
Time
Partial ○ Full ●
Scope ↔ X
Completion ↕ X
• Partial scope – partial completion
delivery
• Progressive addition and/or
refinement of partial parts
Nothing
All
Uncertainty

14. Waterfall Incremental Iterative
Iterative &
Incremental
Uncertainty
Requirements

15. Referencies
• Jeff Patton, 2008. Don’t Know What I Want, But I Know How to Get It.
• Jeff Sutherland, 2010. Iterative versus Incremental Development.
• Steven Thomas, 2012. Revisiting the Iterative Incremental Mona Lisa.
• Patricio Letelier, 2013. Desarrollo Iterativo versus Incremental ... o ¿cuál es la mejor estrategia
para pintar la Mona Lisa?.
• Alistair Cockburn. Using Both Incremental and Iterative Development.
• Wikipedia. Iterative and incremental development.

16. Question & answers

17. Marco Massarotto, Ph.D.
Agile Coach (CSP-SM®)
@MassaMarco
MassaMa