Did they just ignore all the non-rounded rectangles around them? They're everywhere, too, and I fail to see how this does or does not argue for their use.
It's simple if you think about it. Making rectangles with rounded corners takes work. You have to go out of your way. That so many craftsman, engineers, etc. did so is suggestive.
Moreover, looking at a lot of rounded rectangles will have the same effect that the examples in the linked article did. You'll notice that objects with them are more appealing than their counterparts.
That so many craftsman, engineers, etc. did so is suggestive.
In many cases it suggests that leaving a sharp corner, such as on a table, would risk injury to some users. But in general, that something took extra work, says nothing about the rationale behind it. Maybe it's a way of showing off skills; I've certainly seen that in code , where the people did something the hard way for reasons other than "this is what is best for this situation."
Moreover, looking at a lot of rounded rectangles will have the same effect that the examples in the linked article did. You'll notice that objects with them are more appealing than their counterparts.
What I notice is that sometimes they are appropriate, sometimes not. They are not universally appealing.
In many cases they give things an inappropriately childish (childlike?) feeling.
