True Lies Of Optimistic User Interfaces

An optimistic UI is nothing more than a way of handling human-computer interaction. To understand the main ideas behind it, we will stick with our “user clicks a button” scenario. But the principle will be the same for pretty much any kind of interaction that you might want to make optimistic.
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In 97 to 99% of cases when the user clicks a button on a website, the server’s response should be success, with no error.

https://www.smashingmagazine.com/2016/11/true-lies-of-optimistic-user-interfaces/