ABSTRACT
Practice makes perfect. Correcting the overstatement of a maxim: Almost always, practice brings improvement, and more practice brings more improvement. We all expect improvement with practice to be ubiquitous, though obviously limits exist both in scope and extent. Take only the experimental laboratory: We do not expect people to perform an experimental task correctly without at least some practice; and we design all our psychology experiments with one eye to the confounding influence of practice effects.
