Chris Petrilli explains why web UI's are not the end-all, be-all that so many would like us to believe they are:

I’ve been working on an application, for a while, off and on, and have at various points contemplated what the UI would look like. Now, please understand that I’m not Tog or Donald Norman. Instead, I’m simply a user who on occasion notices good and bad design. Most web-based applications are only “good” if you put them in the context of artificially low expectations and the general crap that permeates the market.

Instead, I’ve decided that rich user interaction is critical. Not the kind of stuff that uses XmlHttpRequest, but the kind of thing that uses drag and drop, contextual menus, inspectors, and other generally accepted practices in the UI world. For example, if a user is looking at a set of data, and has a chart open, why should they not be allowed to select and drag that data onto the chart and have the chart adapt to their new data? Perhaps, even it should even ask the user whether to integrate the data, or build a comparable graph with the new data.

Web interfaces have their uses, but there are also areas where they are a huge, huge leap backwards.