In user interface design and software design,[1] the principle of least astonishment (POLA), also known as principle of least surprise,[a] proposes that a component of a system should behave in a way that most users will expect it to behave, and therefore not astonish or surprise users. The following is a corollary of the principle: "If a necessary feature has a high astonishment factor, it may be necessary to redesign the feature."[4]
The principle has been in use in relation to computer interaction since at least the 1970s. Although first formalized in the field of computer technology, the principle can be applied broadly in other fields. For example, in writing, a cross-reference to another part of the work or a hyperlink should be phrased in a way that accurately tells the reader what to expect.
rexx
was invoked but never defined (see the help page).
Cite error: There are <ref group=lower-alpha>
tags or {{efn}}
templates on this page, but the references will not show without a {{reflist|group=lower-alpha}}
template or {{notelist}}
template (see the help page).