A product's look and feel is far more important than people ever think it is. Many people believe that making a UI super shiny is just for consumer products like the iPhone. Since they work on a Industrial or Medical devices it isn't a requirement and it's all about functionality. Well according to this article "In Defense of Eye Candy" you might change your tune when you realize your customers may be far more forgiving and accepting if you have a little glitter to your UI.
Quote from the article :
We want those things we find pleasing to succeed. We’re more tolerant of problems with things that we find attractive.
If you are planning on creating a UI or redesigning one for your current system it is well worth the read.