So, I've been wondering what would be the best technique when users are facing a loading panel.
When we're not sure how long an action would take, it's common practice to use marquee progress bars or progress rings.
But is there any scientific evidence on what the users feel "faster"?
Say an action takes 10 seconds. We can make them feel like 2 seconds or like 30 seconds. What does the speed of the loading screen have an impact on this?
Technically you can't really make the user feel that the progress is going faster unless you can create an expectation first. Let's say you have an indeterminate process, and you show a spinning circle or hourglass, it doesn't really matter how fast you make the animation go because the user doesn't know what to expect anyway.
This is why sometimes text is displayed alongside the indeterminate process (e.g. Loading...) to set an expectation for the user. Another example is the Microsoft Office loading screen that shows the Add-ins details at the bottom left hand corner. For determinate processes, because there is already an expectation from the user (e.g. you are showing how many % is complete or how many documents need to be processed), the user can try to assess the speed of the progress bar relative to the amount of 'progress' remaining.
Here the trick is to try and match the progress bar animation with the progress so that it is as smooth as possible, or even try to exceed the user's expectation so that they feel it is faster. But if you make the progress bar move to 90% to raise then user's expectation then allow the last 10% to take 90% of the time, this is where you will get user frustration because their expectations are not met.
Rather than trying to solve the issues of designing based on perception, my advice is to design based on utility. That is, if the users have to wait, can you provide them with some useful information or let them do something productive during that time. This would provide a better overall user experience and give the users much more benefit.
There are other examples of making something feel like it's "faster than it is" based on the system feedback to a user while actions are happening in the background.
This article points at three things Instagram does to provide feedback to a user instead of making them wait for the process to finish.
http://www.fastcodesign.com/1669788/the-3-white-lies-behind-instagrams-lightning-speed
There are several studies about that and probably the most famous is the one of Chris Harrison (http://www.chrisharrison.net/index.php/Research/ProgressBars2).
Basically a faster progress bar makes the user feels that the process is going faster. To do that you can play with the pulse (in case of a spinner) or also you can animated the inside of the progress bar using backwards moving ribbings which seem faster to users than forwards moving ribbings.
Basically the time will be the same, but you can make the user feels that is less.
