Quality Progress - August 2016 - 63
ONE GOOD IDEA
BY ALEX COMAN AND BOAZ RONEN
This chart offers a visual element for the theory of constraints
QUALITY MANAGERIAL TOOLS are empowered by visual elements such as Pareto
analysis of waste causes.
2. Strategic gating: Screening tasks that
would look when applying TOC to an
IT application development department
charts, control charts, Ishikawa's fishbone
will not be assigned to the system due to
(Figure 1). In step one, an analysis is per-
diagram and others.
constrained bottleneck resources.
formed that identifies system architects
Subordinate the whole system to the
as the constraint.
The theory of constraints (TOC) is a
Step two of TOC is broken into two
popular five-step continuous improvement
bottleneck. All other departments should
method, but it lacks a visual element.
address the bottleneck. Subordination is
parts. The first is identifying sources of
accomplished using the following tools:
waste-bad multitasking, scope creep and
1. The complete kit policy: Prevent the
endless meetings. The second identifies
The gate and gear chart (see a populated
version in Figure 1) is a simple visual tool
that enables quality managers to communi-
bottleneck from processing tasks that
tasks to be eliminated-the system archi-
cate TOC's continuous improvement meth-
lack components essential to successful
tects will no longer be evaluating the cost
of small tasks.
ods to stakeholders and top management.
The gate has two parts: strategic gating,
2. The small batch concept: Break large
Step three is to subordinate the whole
or selecting tasks, and tactical gating, or
batches into small, lean ones to acceler-
system using three different tools. Enforc-
streamlining those tasks. The gear refers to
ate the flow in the system.
ing a complete kit policy will ensure that
exploiting and leveraging the bottleneck. The
3. Drum-Buffer-Rope release mechanism:
only tasks with complete requirements
Pace the whole system according to the
are fed to the architects. Large tasks are
Identify the system's constraints. A
bottleneck and release tasks to minimize
broken into small elements, and tasks are
constraint is any element that prevents the
work in process and increase throughput
fed to the architects using the Drum-Buffer-
system from achieving better performance.
Rope method with a maximum of three
One of the most common constraints is a
Alleviate the bottleneck. The re-
tasks at a time.
gate and gear chart follows TOC's five steps:
Decide how to exploit the con-
source is alleviated by offloading bottle-
The final step in the chart is to al-
neck tasks to non-bottleneck resources.
leviate, or offload, the bottleneck. The
Reevaluate the constraint. If the
programmers will scope small tasks on
straint. A bottleneck can be exploited in
current constraint is taken care of and its
their own, junior staff will replicate work
1. Waste reduction: Reducing the bottle-
throughput increases, another resource
environments for the architects and project
becomes the constraint.
deployment will shift to the operations
neck's waste or garbage time. Waste
Consider how the gate and gear chart
reduction is achieved using the Pareto
IT application development department:
gate and gear / FIGURE 1
Step 3: Subordinate
1. Enforce complete kit:
only treat complete
2. Large tasks are broken
into small elements.
3. The architect should not
work on more than three
4. In the beginning of
the day, the architect
processes small requests.
Step 2: Exploit waste reduction
1. Bad multitasking.
2. Scope creep.
3. Unnecessary meetings.
Step 1: Identify the bottleneck:
Step 2: Exploit strategic gating
1. No costing for small tasks.
Step 4: Offload
1. Small tasks are scoped by the programmer.
2. Replicating the user's work environment
done by junior staff.
3. Deployment to the user done by
1. More examples of using the gate and gear chart for TOC,
along with a blank template, can be found on this column's
webpage at www.qualityprogress.com
ALEX COMAN is a professor of
project management at Tel Aviv
University and the Academic College
of Tel Aviv in Israel. Coman has his
doctorate in IT from Claremont
Graduate University in California.
BOAZ RONEN is a professor of technology management and value creation
at Tel Aviv University in Israel. He has
his doctorate in business administration from Tel Aviv University and
co-authored Focused Operations Management: Achieving More with Existing
Resources (Wiley, 2008).
August 2016 * QP 63
Table of Contents for the Digital Edition of Quality Progress - August 2016
Mr. Pareto Head
Recognize, Rate and Resolve
Station to Station
Quality in the First Person
One Good Idea
Back to Basics
Quality Progress - August 2016