I'm going to soon rant about internal design, and how imperative that is, but that is not what this post is about. This post, is about interfaces.
There is something to be said about amazing interfaces. I am by no means a designer, and I have really no artistic skill. The only artistic thing I do, or am trying to do, is photography. But as an engineer, my brain respects, and expects exceptional design.
When you create something great with code, the public won't really be able to understand that unless it's coupled with good design. If the application feels great, looks beautiful, and is always pleasant to look at, then you've got something. Then you have a success on your hands.
Whenever I've made some new web app, or software app, the very next thing I think about is the icon. I don't know what it should look like, but I go right to my favorite icon guys to make me a beautiful icon.
A good icon really makes your application legitimate.
I think thats the best thing about good design. It makes your work Real. It makes it professional. Sure I can tell people, I made a PHP framework. But if I say, "I made this amazing PHP framework that you can build custom frameworks out of, It's called CornerStone". And couple that with the icon on the left here. Then yea, you want this framework. It shows a level of legitimacy, that your applications wouldn't normally have.
The same goes for websites. having a website with a bad, or mediocre design is just not acceptable. If you want to make it in todays web world, you have to have designs that make people notice the design. Not just pass it by.
You want people to love your company, love your brand, and respect your work. Great functionally is only half the battle, Great design is what brings it all together.
*the icons were designed by iphone-icon.com.