Instructions, mechanical ability and performance.

The role of instructions aimed at non-specialist users was studied. Two groups of 15 students were given the task of mounting a window shade. The first group carried out the task using the manufacturers' original instructions. The second group used an 'improved' version of the instructions. It was found that the 'improved' instructions significantly contributed to the usability of the product, and that the original instructions failed to fulfil their basic aim: to enable the majority of consumers to successfully use the product.