Transcript Document

The Case for Usability
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Usability is more important than ever
Ten years ago, the Web was exciting to
people. Today it is routine. It’s a tool. If it is
convenient, they will use it; if not, they won’t.
With ten times as many sites and probably a
hundred times as many pages, users are less
tolerant of difficult sites.
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What is Usability?
As defined by The International Standards Organization (ISO)
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“The extent to which a product can be used by
specified users to achieve specified goals with
effectiveness, efficiency and satisfaction in a
specified context of use.”
As defined by The Usability Professionals Association (UPA)
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“Usability is an approach to product development that
incorporates direct user feedback throughout the
development cycle in order to reduce costs and
create products and tolls that meet user needs.”
What is Usability?
As defined by Steve Krug in Don’t Make Me Think (2000)
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“Usability really just means making sure that
something works well: that a person of average (or
even below average) ability and experience can use
the thing – whether it’s a website, a fighter jet, or a
revolving door – for its intended purpose without
getting hopelessly frustrated.”
Usability is About…
• Effectiveness: Can users achieve what they need by
using the product?
• Ease of Learning: How fast can a user who has
never seen the interface learn to use it?
• Efficiency of Use: How fast can users complete a
task?
• Memorability: Can users remember enough to reuse
the interface effectively?
• Error Prevention: The best way to deal with errors is
to design the interface so users do not make errors.
• Satisfaction: How much does the user like using the
system?
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Usability is Not Just “Testing”
• Usability is usually considered the ability of a
user to use the thing to carry out a task
successfully.
• User Experience takes a broader view,
looking at the individual’s entire interaction
with the thing, as well as the thoughts,
feelings and perceptions that result from the
interaction.
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Why is Usability Important?
• Design freedom is high in the beginning when
you know the least. Getting smart early on
lets you incorporate good ideas before the
site is frozen.
– Who are my users and how will they perceive the
site?
– What are the users’ goals with the site?
– What areas are critical to overall success?
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Usability is Important Early In the Project
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Usability
In the beginning of a project (research) . . .
• How do users think and work?
• What are the factors affecting user’s tasks?
• What do users want or expect from the design?
• What are the user’s problems or motivations?
In the middle or just before launch (testing) . . .
• Is the design usable?
• Does the design match the way users think and
work?
• Is the design effective, efficient and satisfactory for
the user?
• Can users complete their tasks?
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ROI of User-Centered Design
• 63% of software projects exceeded their estimates
because of
– Frequent requests for changes by users
– Overlooked tasks
• 80% of software lifecycle costs occur during
maintenance phase
• Every $1 invested in UCD returns between $2 and
$100
• 60% of that maintenance work is due to re-work
because user requirements were not clear in the
beginning.
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ROI: Increased Productivity
[ #Users x Uses/day x Days/year x Increased
efficiency x Loaded Salary = Annual ROI ]
Example:
Create web site for doctors/staff to find referrals increases
efficiency by 6 seconds
Assumptions
#Employees
Loaded salary:
Use:
Increased efficiency
500
$40,000 (~$21/hour or $.35/min or $.00583/sec )
10 tasks per day
6 seconds per task
savings
500 employees x 10/day x 230 days/year x 6 sec x $.00583/sec = $40,520
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Usability Doesn’t Have to be Complex
• Usability does not have to be costly and complex
• Good results come from testing no more than 5 users
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Jacob Nielsen, useit.com
Usability Recommendations
• Data Gathering and Analysis
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How do users think and work?
What are the factors affecting users’ tasks?
What do users want/expect from the design?
What are users’ problems and motivations?
• SMN Ease of Referral site
– How do doctors and/or their staff do referrals today? Do doctors do
their own referrals? Is there a referral coordinator?
• Current processes: Do they get on the phone? Use a printed book?
• What are the pain points?
– How would they like to search? What would make their jobs easier?
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Usability Recommendations
• User Testing
– Is the design usable?
– Does it match the way users think/work?
– It is effective? Can the user complete their task?
• SMN Ease of Referral site
– Show working demo site to a group of 5-10 doctors or their
staff.
– Can they complete searches?
– Is it satisfactory?
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