Usability lessons learned : The real cost of bad usability.
Come join us @Confoo for a Scrum simulation using paper prototyping!
Let’s take a very simple example of a very commonly used software that most people use during their work day : the Web browser.
This serves a good example because a web browser is well known by most people and rather simple to use(or should be). For this example we’ll use Mozilla Firefox and the stats published on their website. For everything else we’ll make the estimates as conservative as can be while still remaining realistic.
According to it’s own website*, FireFox is currently being used by 270 million users. For the sake of keeping this example easy, we’ll make the very conservative estimate that only 10 percent of them use it for long period of times at work. That makes this a total of 27 million users. For these few heavy users, let’s pretend that this browser is very easy to use and that users only waste a grand total of a measly 30 seconds a day figuring out things they want to accomplish compared to if it were optimally designed for them. For the sake of this conservative estimate, let’s pretend the average income of these workers is only 10$ per hour and that they work 5 days a week and only do so for 45 weeks per year.
For our example, we will be using the following formulas
Total time wasted in a year in seconds(182,250,000,000) = time wasted per day per employee(30 seconds) * work day per week per employee(5 days) * weeks worked in a year per employee(45 weeks) * number of employees using FireFox(27,000,000)
Total Wasted time in hours(50,625,000) = Time wasted in seconds(182,250,000,000) / Number of seconds in an hour(3600)
Total cost in a year of wasted time due to bad ergonomics(500,625,000$) = Wasted time in hours(50,625,000) * Hourly rate of employees(10$)
This very conservative example should make it clear to anyone that a very small flaw in the ergonomics of a software that is heavily used by a large number of users can have an enormous productivity cost and produce large wastes of money for employers. A very large part of this waste could be prevented or at the very least diminished by the use of proper software ergonomics/usability practices. In following articles in this series, we will publish means and method to help through proper interface design.
*http://weblogs.mozillazine.org/asa/archives/2009/05/firefox_at_270.html
