We've talked a lot on ReadWriteStart about how design is an important facet of the development of a web applications for startups. Last week we provided some advice on how to deal with irate customers who hate your design changes, and earlier this month we talked about how small design tweaks can have big impacts of the use of your site.

The main theme of these posts is that good design is worth the time and effort because it goes a long way in attracting and maintaining users, but really, who is to say what "good design" is? A recent entry on the blog ignore the code by Swiss software engineer Lukas Mathis raises an interesting point about user interfaces and how some users prefer that they maintain their complexity.

They like complicated user interfaces? It seems strange, but Mathis argues that mastering a cluttered interface gives users a sense of superiority. One example of this that Mathis points out is the Bloomberg Terminal, a complexly designed business interface whose users might revolt if it were simplified, as some studies have shown.

"Some complex user interfaces may also give people the perception of having more control," writes Mathis. "Another reason why people sometimes avoid simple devices is that they perceive them as being made specifically for children, or for 'stupid' people."

So how does this apply to Web startup culture? What it says is that not all users are the same. Not everyone is looking for the cleanest and simplest design; some want more features and more complexity. The thing to remember is there is a difference between having a complex interface and having a complicated interface.

Even the simplest of interfaces, Twitter, has begun to add more complexity with new retweet features, lists, trending topics, and more. Aesthetically, "good design" means design that is appealing to the eye, and is easily navigated visually. With this idea, it is important that complex interfaces are well designed so that the users who prefer simplicity do not feel overwhelmed.

So "good design" may be simply design that is both aesthetically refined, and that also serves to aid both novices and power users in easily finding the features they want without feeling over or underwhelmed - balanced, and right in the sweet spot. I would love to hear what people think of this idea, so please let me know your thoughts in the comments.