David Martín-Moncunill, Tutor Professor of the Master in eLearning and Educational Technology at Bureau Veritas University Center.
Usability is present in every product: food packaging, a mobile phone, notes for a university course, software for managing a company or the code of this software itself. In all of them, usability plays a role and can make the difference when the user has to make a decision between several available options.
This is precisely the predominant idea when a person without specific knowledge on the subject hears about usability. Among the concepts that usually come to mind are some such as “easy to use”, “sells more”, “is more beautiful” or even the name of companies such as “Apple”, due to the attention they have paid to the subject at hand.
But usability is a quality attribute that encompasses much instagram data more than that. Let's look at ISO 9241, which defines usability as:
“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 .” (ISO 9241-11:1998)
From this definition we must highlight two fundamental aspects:
Specificity: specific users, with specific goals in a specific context of use.
Seeking effectiveness, efficiency and satisfaction.
As an example of how usability affects even the simplest products, in the image we can see a paper cup, to which a handle has been integrated to allow another type of grip and prevent us from burning our fingers with hot drinks. In this way, we can safely remove the drink quickly from the machine and make way for the next user.
Machine cupPhoto caption: David Martín-Moncunill
Based on the above definition, it is clear that usability is not something that can be easily measured with a specific unit, but that there are a whole series of related attributes that influence it. Not all experts consider the same attributes, but we can consider the following as commonly accepted:
Effectiveness refers to whether the product meets the stated objectives
Efficiency in meeting objectives, reducing time and errors
The degree of satisfaction , the subjective impression left on the user after use
The ease of learning to be able to use it satisfactorily and the memory over time , that is, the capacity of a user to use a product after a period of not doing so.
To measure these attributes, methods and tools are used that are sometimes more quantitative, such as effectiveness, and sometimes more qualitative, such as the degree of satisfaction. Some authors consider that factors such as usefulness and accessibility should be considered as attributes of usability, while others argue that they are simply related, but at a different level.
In any case, what is clear is that if a user is not able to see the usefulness of a product (or service) or if the product is not accessible to a specific user, he or she will not even use it; so in neither case would it make sense to even talk about usability. On the other hand, in a usability study not all attributes are always taken into equal consideration, nor will the improvement of one directly improve another; in some cases they will even have to be balanced, always taking into account the objectives, users and specific context of use.
In addition to looking for an attractive product that is easy and even fun to use ( user perspective ) and that therefore sells more ( business perspective ), the productivity and security perspective must be taken into account, which in some cases could be the most important perspective.
Let's think about the interface that a doctor uses to indicate the dosage of medication to his patients. A mistake in identifying a comma that marks a decimal could mean administering a much higher dose to the patient with disastrous consequences, something that, unfortunately, has happened in reality. A usability study on this interface should consider issues such as preventing the error by performing an automatic check on the weight and dosage of the medication and issuing a warning or even correcting the error automatically.