Rosebud!  

That's only because
they haven't tried to sit on one for more than a minute or two.

ssshhhh !
I'd love to try ...
ssshhhh !
I'd love to try a tugendhat, with arms I suspect its the better sitting chair.

Books
There is a great little book called the Geometry of Design that does a bang-up job of explaining why the Barcelona is almost universally liked (visually, at least)
The first seeds of modernism were a drawing table and a lamp my brother made. The table is a simple rectangle with straightforward joinery and functionality that makes it truly beautiful. The lamp is stained glass, but has a crisp square shade with graphic geometry.