I’ve been working in the web development/coding sector for about seven years or so and I’ve noticed a few recurrent issues that  crop up when creating or redesigning a website:

1. Ease of Use.  Including navigation and readability.  ADA tags/formatting and other helpful tags.  Including the ability to adjust the font size as well. Adherence to information mapping guidelines and “the crow memory” rule I learned way back in high school psychology (basically that people tend to get flustered/confused if more than 7-10 items are presented to them at one time). 
2. Consistency of Presentation. This idea supports ease of use by presenting a predictable and consistent interface throughout the site. This practice also reinforces information transference.  Techniques, such as consistent information mapping, will aid in information retention by “chunking” related design/content objects together.
3. Aesthetically Pleasing. A site that holds interest and is pleasing to look at assists in holding the visitors’ interest longer and encourages them to be regular, repeat visitors.
4. Easy to Maintain. Content should be easy to add/update. If it’s perceived to be too hard to keep the website up-to-date and “fresh” by the appointed staff/admins, the site ends up stagnant – or worse, abandoned.
5. Dynamic.  New and interesting content should be posted on a regular basis in order to retain visitors’ interest and to keep the site fresh. Information on the front page should change weekly (at a minimum).  In order to successfully accomplish this, item 4 (easy to maintain) must be in place.  New content keeps visitors coming back to your site to find out what’s new and news with your site/organization.

I’d be curious to know what other common themes web developers have noticed during their various development cycles.

A Note on “Crow Memory:”

Crow memory was a test to see how many things crows could actually track numerically in their heads.  Using various testing methods, they found that crows could count to and remember up to three items, after that they seemed to just consider items as a group of “many.”  If the tester put out three items, then covered them with a blanket, took two items out – the crow knew there was another item to be removed.  However, doing the same experiment with 5 items and removing four, the crow assumed all items had been removed.  Of course this may all be anecdotal, but it’s the lesson my high school psych. teacher used, and I’ve retained it ever since, some 25+ years later.