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The Multiple Life n Attention is where you put it. How
much focus is your decision n Activities are under your control. When
and how often you move from one another is at least partially your decision
n No choice on multiple projects to which you are assigned
3
Multitasking Projects n You have no choice when and how
many you move between n The waste of effort and time is hidden n There are multiple wrong assumptions
leading managers to believe it is a good strategy to move resources between projects
4
Wrong Assumptions n The sooner you start a project,
the sooner you will end the project n There is no waste in multitasking n Blockages are easily solved by adding
more resources n Resources are relatively interchangeable n Unique skills are easily swapped n Done is at the end of the project
5
Critical Path n Critical Path Method is a project
modeling technique from the 1950’s n Determines the shortest path of
activities to project completion n Determines the “Critical” set of
activities that cannot be delayed without making the project longer
6
Critical path + & -
n Benefits – shortest path to completion n Plans are foiled by resource
management n Developer is to blame, or always
makes the project longer
7
What is Critical Chain? n Critical Path: the chain of tasks based
upon task dependencies, and the shortest time to project delivery
n Critical Chain: the longest chain of
tasks that considers both task dependencies and resource dependencies
8
Critical Chain n Advantages
n Costs incurred later n Time for maximizing learning n Better focus early in project; not too many
activities starting up
n Disadvantages n Just one – no room for slippage in the Critical
Chain, or the end date slips. Mitigate via buffers in the chain
9
Critical Chain n Individual task-level safety buffers are
harmful – better to have a smaller aggregated ‘safety’ at project level (critical path)
n Resource scarcity & skill scarcity n Pressure to show early progress on all
projects leads to the detriment of all
10
Slices vs Layers
n Cross-functional teams eliminate the need for multitasking
n Scrum handles this on an iteration level n Skills shared and learned by more
people over time
11
What’s the source of the problem
n Multitasking among / between projects
12
Multitasked projects n Consider 3 projects requiring 20 weeks
effort each, like this:
13
A B C D E F G H I J
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
20 weeks
20 weeks
Add specialized resources… n Blue: for early 3 tasks n Yellow: for middle 4 tasks n Green: for last 3 tasks
14
A B P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
20 weeks
20 weeks
3 Projects – the Exercise n 3 projects, 3 skill types, fully cross
functional teams
15
A B P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
20 weeks
20 weeks
Exercise: Indiv. Multitasking You are going to execute three projects, first using multitasking, then not. The three projects are as follows: Project 1: Write the letters A to J in the first row. Project 2: Write the numbers 1 to 10 in the second row Project 3: Write Roman Numerals i to x in last row The end result is three rows filled like this: A B C D … 1 2 3 … i ii iii …
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x3 x3 x3 x3 x3 x3
3 projects, no multitasking n Have 3 of each resource type
17
A B P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
20 weeks
20 weeks
x3 x3 x3 Resources:
Resources Constrained n The previous example had all 3
projects in parallel – no shared resources.
n Next – explore 2 cases n Shared resources, no multitasking n Shared resources, with multitasking
18
Shared Resources, Without Multitasking
19
n Now have 1 of each resource type x1 x1 x1 Resources:
n Blue must finish her P1 tasks before going to P2, etc.
Show the time distribution of the work
Shared Resources, With Multitasking
20
n Still 1 of each resource type x1 x1 x1 Resources:
n Blue does a P1 task, then a P2 task, etc. for early start on all projects
Show the time distribution of the work
Value for projects
n Project 1 – An example
n Project 2 – You do it – No Multitasking
n Project 3 – You do it – With Multitasking
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Project value
What is the COST of DELAY for 1 week?
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Project 1
A new product earning $10,000 per week after it’s live.
Project 2
New enhancement, once delivered saves $8,000 per week on postage.
Project 3
Fixes a known defect in a “live” product, causing support costs of $5,000 per week & decreased customer satisfaction.
3 projects, no multitasking n Have 3 of each resource type
23
A B P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
20 weeks
20 weeks
Resources:
$23K
t=0 20
x3 x3 x3 x3 x3 x3 x3 x3 x3
Shared resources, single tasking
24
A
x1 x1 x1
B
Resources:
P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
20 weeks
28 weeks
36 weeks
$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $
$ $ $ $ $ $ $ $ $ $ $ $ $ $ $
$ $ $ $ $ $ $ $ $ $ $ $
$10K/week
$8K/week
$5K/week
Notice the value:
Shared resources, multi-tasking
25
A
x1 x1 x1
B
Resources:
P1 C D E F G H I J
P2
P3
1 2 3 4 5 6 7 8 9 10
i ii iii iv v vi vii viii ix x
48 weeks
50 weeks
52 weeks
$ $ $ $ $ $ $ $ $
$ $ $ $ $ $ $ $
$ $ $ $ $ $ $
$10K/week
$8K/week
$5K/week
Notice the value:
How to Stop This Madness
n Approaches We Love n Rational n Emotional
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Rational n Productivity; the person, the team,
the whole project n Critical path / tasks don’t rule n Start sooner does not equal end
sooner n Adds waste and inefficiency n Done means never having to come
back
27
Emotional n Frustration n Blame n No transparency into progress n No sense of accomplishment n Overtime, extra effort
28
Take Something Back n What will you do now?
29
Further Reading n Eliyahu Goldratt, “Critical Chain”, North River Press, 1997 n Clarke Ching, Rolling Rocks Downhill; Accelerate AGIILE with Goldratt’s TOC
http://www.rolls.rocks/ccblog/2014/8/7/rolling-rocks-downhill-still-coming n Critical Chain Concepts (A tool promotion paper, but very well-written
summary of Critical Chain concepts) http://www.civiles.org/publi/Gestion/Critical-Chain-Concepts.pdf
n Lecture from MIT (Gives case study from ITT) http://web.mit.edu/2.742/www/sylabus/3_14.pdf