定義：

In About Face 2.0, Alan Cooper describes the elastic user as an ill-defined user who’s characteristics change to suit the needs of the developer — sometimes as an expert and sometimes a novice.

避免design for the elastic user的有效方法：

1）創(chuàng)建用戶畫像（personas）；

2）遵循用戶心理模型（mental model of user），也叫做用戶概念模型（conceptual model of user），而不是軟件運行機制的實現(xiàn)模型（represented model of software）。