The business case for usability
The benefits of usability engineering extend beyond improving
the user interface and end user productivity: its beneficiaries
include not only end users but also developers and their companies.
User centred design can reduce software and e-commerce costs
(including development, support, training, documentation and
maintenance costs), shorten development time and improve marketability.
Good usability leads to satisfied, purchasing and returning
- A user-centered approach raised customer satisfaction
with 40% (Gartner, 1992). End users/customers are more satisfied
when a system offers relevant services that match their
needs and expectations.
- Online customers spend most of the time on sites with
high usability (Nielsen, 1998).A majority of customers are
loyal only to a few brands (1-3) and buy repeatedly on these
sites (A.T. Kearney, 2000). Satisfied customers lead to
increased sales for both e-commerce shopping sites as well
as for software products. Satisfied customers stay longer
on sites and consume more.
- Almost 50 % of users do not come back if they found it
hard to find relevant information on the web site (Forrester
research, 1999). Satisfied customers are also more likely
to become returning customers.
Bad usability leads to angry customers and loss in sales
- 82% of users attempted to purchase but gave up as a result
of poor design and usability (A.T. Kearney, 2001). That's
one fifth of every customer trying to purchase. Imagine
your local shopping mall: only 20% of the customers can
find the checkout and the rest give up and drive home.
- 43% of purchase attempts failed (Creative Good, 2000)
and 35% in another similar study (User Interface Engineering,
- 62% of people shopping on the Internet gave up their
efforts on finding the merchandise they are looking for
(Zona Research, 1999)
- Research across all sites showed that visitors couldn't
find what they are looking for as often as 60% of the time
(Forrester and Jupiter, 2000)
- 50% of potential sales were lost on the Internet because
of the users not finding the information they needed (Forrester
The results for e-commerce sites are devastating, and lost
sales due to bad design and poor usability represented a $3.8
billion loss in year 2000 sales only (A.T. Kearney, 2001).
Conversion rate: measure purchases, not traffic
The best measure of a site's effectiveness is the site's
"conversion rate". This metric refers to a site's ability
to "convert" visitors to buyers. For example, a site with
three purchases for every hundred visits will have a conversion
rate of 3%.
Consider a site with a conversion rate of 1.8% and annual
revenues of $100 million. Assume that the sites customer base
is growing 25% annually as more customers come online. With
a constant conversion rate of 1.8%, revenues will be $100
million this year, $125 million next year and $156 million
in two years.
By raising the conversion rate to 2.7% (a modest increase,
far below the industry leaders) through a user-centered redesign
the revenues will increase $50 million this year, $62.5 million
next year and $78 million in two years (Creative Good, 2000)!
It is not unusual that a user-centered approach doubles
the conversion rate and revenues (Nielsen 1999).
10% of Fortune 1000 sites should be torn down because their
usability is so poor they are hurting the company's brand
(Forrester research, 1998). Bad usability causes a bad user
experience. A bad user experience influences the experience
of the brand.
If a site is frustrating and annoying, that's how visitors
see the brand. Also, people who have had a bad experience
with a site typically tell 10 others. An investment in user
experience is certainly an investment in the brand.
Reduced costs for development and maintenance
- If the cost of making design changes is 1x during the
user-centered design phase the same thing would cost 10x
as much during the development phase and 100x as much after
product release (Mayhew & Bias, 1994)
- American Airlines reduced development costs by 60-90%
by making corrections in design phase (Mayhew & Bias,
- Usability techniques allowed a high tech company to reduce
the time spent on tedious development tasks by 40%; at another
company, usability techniques helped cut development time
by 33-50% (Forrester, 1998).
- 80% of all software lifecycle costs occur during the
maintenance phase (Mayhew & Bias, 1994).
- Most maintenance costs are associated with "unmet or
unforeseen" user requirements and other usability problems
- A major computer company spent $68,000 on usability work
to improve a system that was used by over 100,000 people.
The resulting productivity improvement saved the company
$6,800,000, which is a cost-benefit ratio of $1: $100 (Mayhew
& Bias, 1994).
- Poor usability on corporate intranets can lead to poor
employee productivity; investments in making intranets easier
to use can pay off by a factor of 10 or more, especially
at large companies (CIO Business Web Magazine, 1999).
- Other productivity gains may be that less people can
do the same job as many. One company saw its data-entry
staff decrease by a third after usability improvements of
an internal system (Mayhew & Bias, 1994).
Although efficiency is not always the key issue in the usage
of the system it is often important. It is more productive
and efficient if a system is designed to support how users
prefer to work and is guided by usability principles for efficiency.
Productivity improvements have the largest impact on work
Reduced costs for training
- End-user training for a usability-engineered internal
system was one hour compared to a full week of training
for a similar system that had no usability work. As a result
of usability improvements at AT&T, the company saved
$2,500,000 in training expenses (Mayhew & Bias, 1994).
Usable systems are easier more intuitive and require less
training. Every hour cut down on training is one hour more
of productive work and one hour less to pay an instructor.