什么是可用性(Usability)?

可用性是一种产品开发的方法：在整个开发周期中引入直接的用户反馈，目的是降低成本和制造能够满足用户需要的产品和工具。不同的书籍和可用性专家对于可用性有着很多种定义。

有两个国际标准定义了可用性和以人为中心（或以用户为中心）的设计：

“[可用性指的是]产品能够在特定用途的情境下，被特定用户使用，以高效和令人满意的方式达到特定目标的程度。”
—— ISO 9241-11

“以人为中心的设计以这些为特征：用户的积极参与以及对用户和任务需求的清晰的理解；功能在用户和技术两者之间的合理分配；设计解决方案的重复；多学科设计。”
—— ISO 13407

在产品开发流程中加入可用性的商业利益包括：

• 提高生产力
• 增加销量和收益
• 减少培训和支持的成本
• 减少开发时间和成本
• 减少维护成本
• 提高客户满意度

很常见的情况是，组织并不去监测一个软件项目的生命周期总成本。最初的开发经费和日程安排是知道的，但是他们一般都没有监测支持成本有多高，可以归因于什么，多少员工的时间被浪费在了不好用的工具上，以及其它后期制作的因素。因此，有少量预付成本的和较短开发周期的项目会经常得到报偿，即使结果是失败的、无效的、或者是不能用的产品。有很多现实世界中的例子可以说明项目是如何从可用性上获益的；而如果不考虑可用性，项目则会受损。

英文原文：

What is Usability?

Usability is an approach to product development that incorporates direct user feedback throughout the development cycle in order to reduce costs and create products and tools that meet user needs. There are many definitions of usability from books by usability professionals.

Two international standards define usability and human-centered (or user-centered) design:

“[Usability refers to] 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

“Human-centered design is characterised by: the active involvement of users and a clear understanding of user and task requirements; an appropriate allocation of function between users and technology; the iteration of design solutions; multi-disciplinary design.” – ISO 13407

The business benefits of adding usability to a product development process include:

Increased productivity
Increased sales and revenues
Decreased training and support costs
Reduced development time and costs
Reduced maintenance costs
Increased customer satisfaction

Too often, organizations don’t track total lifecycle costs for a software project. The original development budget and schedule is known, but they don’t typically track how expensive support costs are, what they’re attributable to, how much employee time is wasted on unusable tools, and other post-production factors. Thus, projects that have small up-front costs and short development cycles are often rewarded even if they result in failed, ineffective, or unusable products. There are many real world examples showing how usability can benefit a project – or its lack hurt.

译者：Leon Zhang, 数字营销宝典 DigiMarketing.cn
原文：UPA (The Usability Professional’s Association), http://www.upassoc.org/usability_resources/about_usability/definitions_of_usability.html

引用地址: http://digimarketing.cn/?p=341