Beauty or Function?
When it comes to the term “function”, people assume that being beautifully good-looking is not a function.
Let’s start with a sofa.

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I imagine that a good sofa for me is one that is ergonomically comfortable.
I can sit on the sofa reading for a three-hour consecutive without feeling my neck or my back pain.
I find that a low sofa without a headrest is often not suitable for my intended purpose, as I would feel that my neck strained over time sitting on it.
From the pictures above:-
The formal is one which is beautiful to my personal point of view, but fail to provide comfort when sitting for a long hour.
The latter is to my opinion ugly, to be honest, but it provides me comfortable sitting experience with its headrest.
The question of: Beauty or function? Should be much proper rephrased into: Beauty or intended function?