As the technology advances, we get more and more freedom in how we design our websites. While this aspect allows creativity beyond imagination, it also creates dangerous pitfalls that should be avoided. First, you have to accept and understand that you are designing a web-page not a print (poster etc.), which is the most dangerous pitfall for beginner web designers especially for those with a graphic design background. (GripLimited; welcome to poster design 101, great typography but a ton of problems). Then, you have to think like a simple internet user, where will they look, what will they see, can they reach the desired information easily. Know that, not everyone will be as proficient as you are with internet browsing, nor will be able to see your website like you see it.
During the design process, there are mainly 5 issues that you have to be careful with. These are visual placement, visibility\accessibility, navigation, loading times\problems, categorizing\archiving (if used).
Below, I will try to give you some examples of what "NOT" to do. The selected sites are particularly well designed however due to one of the facts above, each suffers major problems in usability.
Visual Placement - or in this case Visual Mess:
This is what I would like to call hammering the visitor. I don't even understand what the page is about, nor where I should click.
Nicely done, but what am I looking at? There is so much going on, stuff moving on its own. It is impossible to understand what is a link and what isn't. A navigation disaster as well. Plus on smaller screens, it re-sizes itself, I can't even imagine browsing this site on a netbook.
Visibility\Accessiblity - or in this case Invisibility:
Incredibly fun and innovative design, yet an overkill due to the ridiculously big design. It gets tiresome to drag yourself around, not knowing what is where.
Innovative design and yet again too large for its own good, it is hard to understand what and where is content. Plus the site scrolls from bottom to top and the scroll is at the right bottom. Also too much content at one page, it takes quite long to load.
Navigation - how will I browse?:
Where to begin? This site is a lesson by itself. Disturbingly long load time, no proper menu (just a bunch of images that bring out names that don't mean anything). Slow and jagged transitions on images. Again more load times for new pages. And marvelously, you have to go to a new page to actually shut off the sound.
There was on thing that wasn't on Toyota's mind while designing this beautiful website, navigation. It is really unsatisfying going over those numbers on the bottom to actually see where they might be linked to.
Along with no proper navigation, it also takes quite a while to load. Add to this, the fact that there is no way whatsoever of skipping the introduction animation and you get a beautiful and yet useless website.
Categorizing & Archiving - you have to create an intuitive interface so that the visitor can find what he/she is looking for easily... or maybe you don't as in the following cases:
This is the pillar of confusing categorization. Just click one of those stripes and see what happens, how could anyone find what they are looking for over there.
Another very confusing categorization, just move your mouse pointer to the right side of the page and you will see.
I hope this gives you a good perspective on what to consider when designing for web. Good and innovative design is very important but overdoing it results in losing visitors which I guess no one would want.