Does Progress Bars’ Behavior Influence the User Experience in Human-Computer Interaction?

Background: This research focuses on the satisfaction and waiting times perceived by a user during the moments where the interaction between the user and the system is temporarily interrupted (file download, setup of a program, etc.). These waiting times are often sources of anxiety and irritation. They go usually with the presentation of an animated progress bar, allowing the user to visualize the status of the ongoing process. The objective of this research is to study the impact of several progress bars by varying the progress behavior with three different speed. Methods: Three progress bars were tested, each of them having the same display duration of 10 seconds but with different speed. The first progress bar having a speed-up behavior (the progress bar fills to about 30% during the first 5 seconds, then fills completely as it accelerates), the second a slow-down behavior (the progress bar fills to about 70% during the first 5 seconds, then fills completely when decelerating), the third a constant behavior (the progress bar keeps a constant filling rate during the 10 seconds). Eleven hundred twenty seven distinct subjects (controlled IP) were involved, including 105 women and 1022 men. The mean age of the sample was 24.9 years (SD=7.11). Each subject has to play with an online game, which was a pretext to present a standby screen of 10 seconds when one of the three progress bars were displayed in a random manner. Results: The results confirm the existence of a causal link between the perception of waiting time and satisfaction. In addition, a progress bar that follows a slow-down function is significantly more appreciated by the users. An ANOVA-test applied to the comparison of means for each of the progress bars shows that there is a significant difference in the satisfaction of waiting for durations (F(2, 1124)=3.003, MSE=1.099, p=.050, np2=0.270). On the other hand, there is no significant difference in the perception of waiting durations. Conclusions: Our results show in our context of experimentation that a progress bar with a decelerating filling rate provides greater satisfaction than a constant progress bar or a speed-up bar. The results may provide valuable information for the design of human-computer interfaces and for the improvement of user experience. Thus, beyond varying waiting time duration, different levels of users’ arousal could be introduced as well as the user feedback with information relevant to the ongoing processes.