Prototyping tools have played a huge role for user interface design in the last decade. According to the usability research conducted by Jacob Nielsen in 2002, the return on investment on interface prototyping tools was over 130%. A more recent indicator, according to the report of 2008, is a lot more humble and barely goes over 80%. Why is the ROI on user interface prototyping tools declining even though their popularity seems to be increasing?
One way to explain the declining ROI on user interface prototyping tools is that user interfaces have changed dramatically since the beginning of the century. Back then some of the interfaces were so painfully bad, with bright backgrounds and irrelevant images, that even mediocre prototyping tools could improve the designs a lot, which is why the returns were much higher with less effort. Usability flaws were so big that anyone using an interface prototyping tool for improvement became a usability hero. Today, user interfaces are becoming increasingly elaborate as well as user friendly, which is why usability errors are harder to trace.
Another reason why the ROI is declining may be that competition in user interface design is getting tougher. It takes a lot more skill and effort to create a winning user interface. E-commerce websites, for instance, are using prototyping tools to help create user-friendly product search and shopping carts to convert more of their visitors. Despite competition, the budgets spent on usability have not changed much. According to Jacob Nielsen’s research, usability budgets constituted 10% of projects’ budgets in 2002, and approximately the same percentage in 2008.