A beautiful website for Porsche/Apple/Stripe and other highly-regarded products inspire confidence.
Apply this same design to Dell's website and people won't take it seriously.
In my recollection, Stripe's focus on aesthetic design didn't begin until the core problem of simple credit card processing for developers had been solved. Once they gained trust with their customers as a brilliantly-engineered product, beautifully-designed UI's followed.
A product that cuts short on presenting a polished product on the outside, may very well have the same ugliness to its internal components.
Or, as sometimes happens, 90% of the effort went into the design, and the product itself is crap. That happens too. ;)
If this were true, we wouldn't need to be constantly reminding people to not judge a book by its cover. That said, great novels have been judged so by their content, not their cover. So it seems that the whole of it is more complicated than any part.
Maybe something like: It must look good to get attention. It must be good to keep it. But if something that looks better comes along, it will steal attention, at which point you can only recover it if you remain better.
But that doesn't make a snazzy saying.
I'd rather have a website that works and doesn't have a gorgeous UI. Sure, ideally we could have both, but these modern web UIs are quite unreliable in my experience.
Design is absolutely essential... but only if everybody else is doing it.
(In that sense, it is a bit like advertising.)
Design and advertising are distorting the free market. We cannot see if one product is better than the other by looking at its design. We can only conclude that one company has put more effort into the design of a product, than another company and from there we often end up with the fallacy of concluding that one product must be better than another.
However, advertising and design nowadays only show that one company has bigger pockets. Or, in other words, money is spoiling (through design and advertising) the evolutionary properties (in terms of quality) of the free market.
From the moment that you acknowledge that red text on a blue background is hard to read and makes a product genuinely worse, you must acknowledge that the design of a product is a legitimate part of a product.
Design and usability go hand in hand, and _of course_ a product's usability is a genuine part of the feature matrix of products. Sure, some design differentiation is "marketing" , but you also have designs that genuinely make a product better/worse.
If the Stripe app was well designed, but did not provide the user enough information to accomplish his or her goal, it would be useless.
The opposite is not true. You can have a poor design that can still be useful if the content is valuable.
I'm not trying to diminish the import of design, but your claim that they are of equal value is false.
The whole thing is beautiful, from the low level of Go, up to the CSS.. it's not just a nice cover on top (like many other products)