1. Overload The Site (ads, images, clutter, etc.)
Having too many images and ads on a page will make the site unattractive and distracting.
You don’t have to fill every space, having an image or two makes a better and cleaner impression. For example, reading a magazine article is easier when you don’t have a picture or ad every two paragraphs. You should have white space between text, photos or navigation.
2. Use Flash Intro or “splash” Page
(I could create a post on this alone…and probably will). Any professional designer or developer will tell you that Flash intros are a pain. That isn’t the reason to use them however.
One, they are not SEO friendly.
Two, the size of flash is considerably higher than just a graphic, it takes time to load.
Three, most people don’t want to wait to enter a site, it’s more likely they’ll click the back button.
What if you came across two vending machines? One, you could just enter your money, make your selection, and get your product. The other required you to wait for a presentation to load, then play a 30 second presentation about their products, and then you can buy something. Which one would prefer?
3. Stray From Common Navigation
Why re-invent something when it’s already been done. Being too fancy with your navigation is an easy way of turning off the visitors. Everyone is familiar with the two types of navigation, across the top or to the left. It’s like if an auto maker wanted to start putting the shift lever or knob on the left instead of the right. People like to stick with what they know.
4. Having unnecessary gadgets (widgets, scripts, counters, blinking text)
Just because you came across a new script or feature doesn’t mean you have to use it. Widgets should be used only if the visitor can get useful information or use out of it. When you visit a site, you want to find the information quickly and not have to sift through meaningless junk. Counters displayed on the site are a big no-no. The best way to keep track of visitors is to implement some type of analytics in a behind-the-scenes script.
5. Music without controls
Normally you see music with flash (see flash above), but if music is used to enhance the visitors experience, you MUST give them an opportunity to turn it off.
6. Use Images instead of text
When displaying content, text (which you can select and copy) has to be used. Images can allow you to use different fonts and colors but it will punish your SEO statistics. To the search engines, as far as they’re concerned, you don’t have any text. How can they rank your site if they can’t tell people what your site consists of?
7. Use crappy photos
Using bad photos for a website is like using bad photos for anything else you’re trying to market. Imagine seeing a company’s business card, flyer or brochure with small, faded, pixilated, or stretched photos. That just shows the company doesn’t care about its image.
8. Use heavy images
Using large images for a site is risky. If large images are going to be used, optimize them for the web. Reduce their file size so it doesn’t take forever to download. The slower your site is, the faster a visitor is inclined to move on to the next one.
9. Use tables for layouts
Tables are meant for one thing, formatting text. Don’t use tables to design your site. This is a true mark of a developer that doesn’t have the skills to properly develop a site. Tables are terrible for updating or maintaining in the future.
10. Use multiple colors
A good website should have a consistent and clean looking color scheme. You shouldn’t have more than three main colors. Here is a bad example:
You should have contrast, just not too much. Also, too much of one color is also a huge mistake, white space is a good thing.
(also see “10 Things to do When Designing a Website“)