Quality Progress - January 2016 - (Page 49)
BACK TO BASICS
BY RAJEEV CHADHA
Why Ask Why?
A lesson on latent causes
FIVE WHYS is a fundamental and simple
be influenced at the initial stage. Their
me with one of his chronic issues that was
method of root cause analysis (RCA). Asking
corrective actions need top management
causing big losses and countless customer
"Why?" is formalized by some industries and
interventions to change programs, policies
complaints about the product quality. We
is a favored technique of many reliability, Six
did an initial five whys analysis (see Figure
1), and there were clear indications of a
Sigma and manufacturing professionals. By
We will focus solely on latent causes
repeatedly asking the question "Why?" you
because identifying them early can prevent
latent cause. The engineer got his answer
can peel away layers of the symptoms that
other organizational issues. Although
as to why the product, though greatly
lead to a problem's root cause. Often, the
intensive investigation and what may seem
under-specified, was still running.
ostensible reason for a problem will lead you
like a tedious amount of evidence collection
As explained in the diagram, solving
to another question. Although this technique
may be required, these steps are imperative
the physical root cause of the issue is not
is called five whys, you may need to ask the
in earning managerial approval to proceed
sufficient in many circumstances and that
question fewer or more than five times be-
with corrective action.
is why it is important to influence management about the latent and systemic causes
fore you find the issue related to a problem.
Some believe that there are five levels
Dealing with latent causes
of the problem you are tackling.
Organizational plans are the how-to doc-
of causes: cause effect, physical cause,
At the organizational level, latent causes
human cause, systemic cause and latent
are the conscious decisions made regarding
uments that show how company operations
cause. If the cause is physical or human,
whether to do certain things. Most of the
are performed. If we want to know how
it can be corrected easily. Systemic and
time, these causes do not include simple
the production, quality assurance, human
latent causes, on the other hand, can only
employee mistakes (such as forgetting
resources or marketing in an organization
a step in a process), nor do they include
will take place, the plan will explain those
repercussions of inadequate training. These
processes as well. So, to unfold the latent
kinds of issues will be discovered and dealt
cause of a chronic organizational problem,
with when probing for latent causes.
you may need to involve upper manage-
Latent root cause
example / FIGURE 1
shipped to the customer,
and discounts were given
every time. Why?
Product was nonconforming
was bypassed and product
cannot be refined further.
Why was the process bypassed?
are insufficient to
run the equipment
effectively. Repair of
Current repairs are
insufficient to run
effectively. Why is
the equipment not
Replacement needs capital,
but capital is not available
for this project. Why?
One automotive supplier addressed
ment. The simplest approach is to develop
multiple customer complaints regarding a
an activity hierarchy and unveil the latent
plastic molding die and eventually altered
root cause so that management can change
the die to resolve the issue. The die's life
the operational plan.
cycle was ending, and the team was still
said, "If you don't ask the right questions,
human levels. The actual issue regarding
you don't get the right answers. A question
the faulty plastic parts used in the die-
asked in the right way often points to its
holding containers was, in fact, the latent
own answer. Questions are the ABCs of
cause. The tool was old and needed to be
diagnosis. Only an inquiring mind solves
replaced, but neither management nor the
customer wanted to invest in the production of an entirely new tool.
Industrial latent causes are nothing new,
but as an RCA specialist, it is important
Current capital decision makers
see replacement as low priority.
Product is still selling and equipment
can be replaced on a later date. (This is
the latent systemic root cause
of the issue.)
As famous author Edward Hodnett once
tracing the root cause at the physical and
to encourage management to accept the
reality of these causes so it can decide what
corrective action is necessary.
A refinery chemical engineer approached
RAJEEV CHADHA is an industrial
technology advisor for the National
Research Council Canada in Alberta,
providing advisory services in mining,
manufacturing and chemical processes. He has a master's degree in
systems management from the Indian
Institute of Technology Delhi in New
Delhi. A senior member of ASQ, Chadha is a certified Black
Belt, and quality engineer and auditor.
January 2016 * QP 49
Table of Contents for the Digital Edition of Quality Progress - January 2016
According to Plan
Use Your Head
Stakeholder Management 101
All About Data
Eight Simple Steps
Which Six Sigma Metric Should I Use?
Turning ‘Who’ Into ‘How’
In the Beginning
Outputs and Outcomes
That’s So Random—Or Is It?
Improving a System
Putting It All on the Table
Know the Drill
It’s Fun To Work With an F-M-E-A
Solve Problems With Open Communication
Tell Me About It
Separate the Vital Few From the Trivial Many
To DMAIC or Not to DMAIC?
Breaking It Down
1 + 1 = Zero Defects
Curve Your Enthusiasm
Make a Choice
What Is a Fault Tree Analysis?
Successful Relationship Diagrams
The Benefits of PDCA
Return on Investment
The Art of Root Cause Analysis
Why Ask Why?
Get to the Root of It
Checks and Balances
Clearing SPC Hurdles
Supplier Selection and Maintenance
Building a Quality Team
Plan Experiments to Prevent Problems
Quality Progress - January 2016