Indeed, there's a balance to strike between retraining and familiarity. _The Humane Interface_ discusses the balance between delivering something with "optimal

Indeed, there's a balance to strike between retraining and familiarity. _The Humane Interface_ discusses the balance between delivering something with "optimal usability" from an objective and scientifically validated standpoint vs. delivering a product the target audience can quickly familiarize themselves with and transfer their existing domain knowledge to. So, while the Canon Cat may be a revolution in word processors, the average user will do better with something similar to Microsoft Word because they know it and can apply what they already know rather than learn a whole new way of word processing.