1. A call center aimed to reduce its average call handling time of 150 seconds without hurting service quality. 2. Using lean tools, it identified five main causes of long calls like slow typing and unnecessary call steps. 3. After implementing solutions like streamlining processes and improving training, the call center reduced average call time to 120 seconds within three months, allowing it to handle 20% more calls with the same resources and saving an estimated $2.5 million annually.

1. Every
Second
Counts
In 50 Words
Or Less
• A call center needed to
reduce its average call-
handling time without
hindering quality of
service.
• Using lean, it identi-
fied and addressed five
main root causes of
longer calls.
• In three months, the call
center reduced its aver-
age call by 30 seconds,
with potential annual
savings of $2.5 million.
IN BUSINESS, we often say every second
counts, but we seldom experience it in reality. In
today’s competitive market, especially in matured
industries, we can’t gain sustainable profit just
through revenue because cost plays a vital role in
overall profitability. It’s a simple equation:
Profit = revenue – cost.
You can gain sustainable profit either by in-
creasing revenue or by reducing cost. In a mature
market, we can do both.
by Sami Saif
How one call center applied
lean and Six Sigma to reduce its
average call-handling time

2. February 2016 • QP 25
LEAN SIX SIGMA

3. QP • www.qualityprogress.com26
The traditional concept of cost savings evolved in
the manufacturing industry, where savings tend to be
achieved by applying various lean tools. For example,
kanban can reduce the cost of inventory. Spaghetti
diagram analysis identifies motion wastes so the best
possible physical layout for efficient operation can be
used.
During the last decade, the concept of cost savings
has not been confined to the manufacturing industry.
Lean methods are now being applied in service indus-
tries, and many organizations are benefitting from this.
Lean even can be applied in call centers, and many call
centers have begun reaping the rewards of applying
these methods.
Lean in the call center
Customers want three things when they call into a
hotline: a good attitude, fast service and accurate ser-
vice. In other words, a customer wants an empathetic
agent who can give accurate information efficiently.
The concept of lean hits the efficiency part, but you
still must ensure the service quality (good attitude and
accurate information) remains intact.
I work for a leading mobile phone operator in Ban-
gladesh, and I applied lean in its call center. The call
center received about 100,000 to 110,000 calls every
day, and its average handling time was about 150 sec-
onds per call. The organization had a customer base
of 40 million that was growing at an annual rate of
20%. The customer base and incoming calls to a call
center are positively correlated, meaning increasing a
customer base leads to an increase in calls to the call
center.
Although self-service channels (e-care, website and
interactive voice response) were available, the orga-
nization’s customers preferred calling into the hotline
and were more comfortable talking to human agents.
About 1,500 employees worked around the clock to
manage this huge call volume. Of those, 600 were full-
time employees who worked eight hours per day.
To manage the increasing number of calls to the call
center, there was no other option but to enhance call-
handling efficiency because increasing manpower to
keep pace with increasing call pressure was not con-
1. Slow typing
speed
2. Nonvalue-
added steps
of call-handling
process
3. After-call
customer
insight
capture
4. High
frequent
services with
high AHT
5. Slow
learning
curve for new
employees
HIGH AVERAGE
CALL-HANDLING
TIME
Savings from one less
second in call center / TABLE 1
Full-time employee (FTE) time contributions:
• Per day = 25,200 seconds (one FTE productive time: 7
hours/day)
• Per month = 554,400 seconds (one FTE productive time:
22 days/month)
Time savings:
• Calls/month in call center = 3,300,000 (On average,
110,000 calls/day)
• One-second savings per call = 3,300,000 seconds overall
savings per month
• FTE savings/month = 5.95 ~ 6 (3,300,000/554,400)
FTE cost:
• 1 FTE/month = $1,231 (CAPEX: PC, software license +
OPEX: salaries, utilities, rent)
• Potential savings/month = $1,231 × six FTE ~ $7,326
Causes of high average
call-handling time / FIGURE 1
CAPEX = capital expenses, OPEX = operating expenses

4. February 2016 • QP 27
sidered a cost-effective option. So, our challenge was
to find ways to receive more calls with our existing
manpower without affecting customer experience or
service quality.
Benefits
In the telecom industry, every second means money,
and in a call center, every second saved means the abil-
ity to serve additional customers. Table 1 depicts the
significance of saving one second per call in a call cen-
ter. It shows one second saved per call is equivalent to
the cost of six full-time employees.
Root causes
Considering the benefits of applying lean in a call cen-
ter, we initiated a lean Six Sigma project. In the ana-
lyze phase of the Six Sigma define, measure, analyze,
improve and control (DMAIC) method, we identified
several potential causes through data analysis and fo-
cus group discussions.
We applied the five whys method and used an
Ishikawa diagram to do this. We also validated a few
causes through statistical analysis and prioritized five
root causes of high average call-handling time in the
call center (see Figure 1):
1. Typing speed. Agents with a slow typing speed
tend to have a high average handling time.
2. Nonvalue-added activities in the customer
service process. These included long greetings
and a long call hold time, which could have been
used for cross-selling or up-selling. Instead, agents
were cross-selling and up-selling separately, which
added to the call-handling time. Another nonvalue-
added activity was a long, unnecessary summing
up, when agents reconfirm the customer’s query
and the solution provided before ending the call.
This added five to six seconds to every call.
3. A problem in the call insight capturing pro-
cess. After every call, agents must capture the in-
sight. This means, agents must input the reason for
the call into the customer relationship management
(CRM) system. The CRM system is used for man-
aging all customer interactions with the call cen-
ter. We found the process of capturing the insight
lengthy, requiring the agents to go through four to
five steps.
4. Services that took a long time and had high call
frequency. A few high-frequency services that took
a long time to serve include internet services, offer
campaigns, personalized ring-back tone services,
and billing and use information.
5. A slow learning curve for new employees. From
data, we found it took at least 12 months for a new
LEAN SIX SIGMA
Outcomes of focus group
discussions / TABLE 2
SL Root
Causes
Improvement Initiatives
1
Slow
typing
speed
Established minimum required typing speed of 25
words per minute for contact center agents.
• Trained existing employees on the use of shortcut
keys and faster PC maneuvering.
• Incorporated typing speed as a criteria during
recruitment.
2
Nonvalue-
added
steps
of call
handling
process
Eliminated a few nonvalue-added activities and made
the call handling process more efficient.
• Incorporated greetings into interactive voice
response (IVR) and shortened the greetings for
agents.
• Proposed to use the call hold time by cross-sell/
up-sell during call hold.
• Stopped providing summing-up dialogue that is not
value adding for customer.
3
After-call
customer
insight
capture
Simplified the insight capturing process in customer
relationship management system by reducing it from a
four-step process to one step. Initially, agents needed
to navigate through multiple windows of CRM to
capture the reason for a call. As a part of improvement
initiative, we changed the interface of insight capturing
module of CRM and ensured that insights can be
captured in one window and with a single click.
4
High
frequent
services
with high
AHT
Promoted self-service channels (IVR, e-care) for few
high-frequency services to divert the calls from the
hotline to those self-service channels. E-care is a less
costly channel than call center. Cost/visit at e-care is
only 10 cents, whereas the cost/call at call center is 40
cents. We promoted our e-care channels to customers
by offering free data volume and free value-added
service if they took services from e-care. It worked
because the e-care visits increased by 10 times,
and the incoming calls in call center also reduced
significantly. It also reduced the overall channel costs.
5
Slow
learning
curve
of new
employees
Improved the new employee learning curve from 12
months to three months with focuses on:
• Simulation-based training session.
• Practical case-based training.
• More on-the-job training than traditional classroom
training.
SL = service level, AHT = average call-handling time

5. employee to reach the standard call handling time.
Before that time, his or her average was high and
unstable.
Improvement initiatives and results
In the DMAIC improve phase, we conducted focus
group discussions to identify potential solutions to the
validated root causes of the problems (see Table 2, p.
27).
After implementing the solutions, within three
months, the average call handling time has been re-
duced to 120 seconds from a previous 150 seconds.
Consequentially, the interactive voice response
call waiting time was reduced, and the call center
can now receive 20% more calls with the same re-
sources.
The initiatives potentially eliminate the need for
178 FTEs, which is equivalent to about $220,000 per
month or $2.5 million per year.
Call handling time vs. SQI
After implementing the solutions, we wanted to see
whether they affected our service quality index (SQI)
because our objective was to ensure call handling ef-
ficiency without hampering the SQI.
The SQI is calculated by a quality assurance (QA)
team that listens to recordings of 10% of the total
calls per month and evaluates agents’ performance.
The QA team rates each call on a 0-100
scale (60% on behavior or soft skills, and
40% on knowledge and accuracy of deliv-
ery). Figure 2 depicts that efficient call
handling or lower AHT actually leads to
a higher SQI.
Continuous improvement
In business, we can’t be complacent. Im-
provement must be continuous. In a call
center, we continuously look for opportu-
nity to improve things as new processes
evolve to keep pace with a changing busi-
ness environment.
In our organization, we have a dedi-
cated Six Sigma expert who maintains a
process performance dashboard to track
different process performance indicators
such as average call-handling time, SQI
and waiting time, and who initiates lean
projects or kaizen.
This helps our organization maintain a
continuous improvement culture. QP
QP • www.qualityprogress.com28
LEAN SIX SIGMA
0-3
116
118
120
122
124
126
128
130
4-6 7-12 13-24 25-36 36+
94
93
92
91
90
89
88
87
86
85
84
Job tenure (month)
AHT(seconds)
SQI
AHT SQI
Regression analysis: AHT vs. SQI
The regression equation is
AHT = 269 - 1.60 SQI
Predictor Coef SE coef T P
Constant 269.14 30.42 8.85 0.000
SQI -1.6049 0.3336 -4.81 0.000
S = 3.37729 R-Sq = 59.1% R-Sq(adj) = 56.6%
From statistical analysis (regression
equation), we also found that AHT and
SQI are negatively correlated. That
means lower AHT leads to higher SQI.
AHT and SQI are
negatively correlated
AHT  = SQI 
Average call-handling time vs. service
quality index / FIGURE 2
AHT = average call-handling time
coef = coefficient
P = p-value
R-Sq = root square
S = standard error of regression
SQI = service quality index
SE coef = standard error coefficient
T = t statistic (coefficient divided by its standard error)
SAMI SAIF is a customer-centric
transformation program manager
at Grameenphone Ltd. (a subsidiary
of Telenor Group) in Dhaka, Bangla-
desh. He has an MBA from North
South University in Dhaka. Saif is
a senior member of ASQ and an
ASQ-certified Six Sigma Black Belt.
He is also a Project Management Institute-certified project
management professional.