Most probably not, at least in my programs I’ve never made a flag, because my delays are usually no more than 3 seconds anyway

I’m pretty sure it’s either a myth (that it doesn’t work) or some US-centric thing, because when I worked as a delivery guy, I used to go through probably hundreds of different elevators in high-density residential buildings, and most of them have doors that stay open very long to allow baby strollers and heavy appliances to be placed inside, and on pretty much all of these the door closing button works, immediately closing the door

This is what I and many other programmers have done (not the removal, but fake delays), because it improves user experience, actually:

1.When the user clicks a button that should take long in their mind (like uncompressing a zip file etc) but is actually fast, it might seem like something is wrong and it didn’t work

2.When the user transitions between layouts of the application, if it loads everything too fast it will look too abrupt, a fake delay will be made here if a transition animation is not possible/doesn’t fit