Labor Illusion

We have been to a restaurant lately where we waited for our food for longer than we could ignore.

HBR study shows that customers do not particularly hate waiting for your applications to process, as long as you show them what you working on, or, at least, what you pretend to be working on.
This is called labor illusion. It's a demonstration of effort, whether literal or not, expended to meet the customer's request.

Apple voice recognition software will mimic the sound of typing while processing, ATM shows the images of counting bills while customers are waiting for their cash.

Funnily, experiments show that customers who endure waits but see a running tally of tasks end up happier than those who don't have to wait at all!

With this, I encourage all restaurants to have open kitchen, or bar setting that customers can see the cooks work. Even if you can't bring up dishes quick enough, labor illusion that cooks work hard (even if they may not be working on your order) helps more than giving customers another free loaf of bread.

In software products, don't be shy to take more time at processing. Just remember to show customers what you are doing behind the scene. Maybe show a magnifying glass over documents in an insurance claim application, or, an animation of sifting through expensive cars in processing a used car search query.