Design matters. I don't just mean software design, like what objects you'll have or what the interfaces will be or what database tables you'll use. I don't just mean planning before you code. I also mean visual design. I'll tell anyone who asks that I'm a grey-boxes-on-a-grey-background kind of girl, but that's mostly about my skills, not my aspirations. I can tell good looking from not so good looking, and I do get that being good looking makes a difference, at least for applications.
I read an interesting article called In Defense of Eye Candy and it has some good examples - mostly oriented towards web sites, but not entirely - about making it clear that a button is a button, and about the tone and mood you set with your design decisions. Worth reading.