Everything that has ever been designed is usable. At the very least, it was usable to the person who designed it. If you intend to have more than just the designer use it, you will need to take usability a little more seriously.
Features cannot be designed in a universally usable manner. A usable design fits naturally and seamlessly into the work pattern or expectations of the application’s users. Therefore, for every different work-pattern or expectation, there is a different usable design.
From a broad perspective, two classes of usable design exist:
Walk-up-and-use
When people think of usability, they think of a walk-up-and-use system. Almost all publicly available internet applications fall into this category (or should fall into this category). This system can be used with no training and with little help. The application should, in essence, hold the user’s hand. It will always take longer to perform the same action with a walk-up-and-use system as it does with a walk-up-and-learn system.
A good walk-up-and-use system has the following qualities:
Walk-up-and-learn
When you have an application that is used by your audience at least several hours everyday, then you have a walk-up-and-learn system. When designing this application you will be designing for experts. They need a system that is geared toward speed and efficiency. Because of this, some training will be required.
It may seem undesirable to have any training, but think of this simple cost benefit analysis: It will always be quicker to use a walk-up-and-learn system in the end. Therefore, the more streamlined and quicker the system is to use, the more training it will require to use it.
A good walk-up-and-use system has the following qualities:
Final thoughts
While it is possible to use a walk-up-and-use system in the case where a walk-up-and-learn system is required, productivity and performance will be sacrificed for the reuse of systems. The converse is also possible, but in that case the novice users who are forced to perform on a walk-up-and-learn system will have a very low success rate.