Is beautiful really usable?

“What is beautiful is useful” showed that aesthetics and usability are highly correlated. Since then, those findings have been confirmed by some, but rejected by other studies. We also still don’t know why they’re correlated. A newer experiment conducted by Tuch et al. sheds more light on the relation between the two concepts.

There aren’t many experimental studies that manipulate aesthetics and usability as independent variables. The ones that do are typically correlative in nature.

In other words: any claims about causal relations between the two concepts are largely based on theoretical reasoning only. It’s therefore still unclear if and when aesthetics influence usability, and vice versa.

Tuch et al. therefore conduct an strictly controlled laboratory experiment that independently manipulates aesthetics and usability.

The overall idea of the experiment is pretty similar to the one described in last week’s article.

Four online shops were implemented for the experiment. All shops are functionally identical to each other, but have a different combination of usability and aesthetics levels, which are obtained in pretty subtle ways:

• Usability and information architecture are strongly related concepts. Usability levels were therefore manipulated by modifying the product hierarchy: the high-usability version has an easily navigable hierarchy with labels that make sense, whereas the low-usability version includes a lot of ambiguity.

• The aesthetics level was manipulated (side note: You can find an example of such a manipulation in the screenshots below.) by taking good-looking professionally designed templates, and modifying the colour of some decorative elements.

A total of 80 participants were recruited for the experiment and assigned to one of the four online shops. Each participant was asked to perform a series of tasks. Perceived usability and aesthetics were assessed both before and after participants worked on their tasks.

Given all that was known from previous studies, one would expect that good-looking versions of the online shop would receive higher usability ratings from participants. Surprisingly, no such effect was found: perceived usability was solely affected by the actual usability of the interface.

Usability on the other hand did have a significant effect on perceived aeshetics after participants had used the shop to complete a few tasks, as did actual aesthetics.

A possible explanation for this effect is that a frustrating usability experience results in a negative affective experience, which in turn results in lower ratings of perceived aesthetics.