The user interface is important. It is the ambassador for your system, your advertisement, your customer service rep. So you need to make sure it’s customer-friendly. Put simply, your system needs to do what people expect it to do. When I click on a link with a roll-over effect, it will take me to a different page. When I click on a button, it should trigger an action. So we stick to these standards, even if they’re not the best usability-wise, because we are creatures of habit and even little changes hurt.