Courtesy of Programming-Designs.com
1. Free templates
This is the most obvious sign of a lazy webmaster/web designer. Using a free template for your site is neither professional or justifiable under most circumstances. Free templates do have their place, but will be frowned upon by many.
2. Using web scripts / software without making changes
It's one thing to download, install, and custom modify a script to fit your site - but it's a whole different story when you leave the script at its default settings. Two prime examples include installing forums using its default theme and using content management systems with its default settings/style. I mean come on, the majority of the work has already been done, take some time to add some personal flavor to it.
3. Designing without CSS
As many people have transitioned to the use of CSS, many have also failed to make the shift; whether it be from lack of knowledge or laziness - there is still no reason not to make the move. CSS not only improves page loading speed, but ultimately saves precious time and better organizes a website.
4. Code doesn't validate
A great webmaster/web designer will ensure that their code is compliant with W3C standards and keep their code consistent, organized, and up-to-date. If a web designer doesn't know about web standards, they obviously haven't taken the time to do much reading on the subject.
5. Excessive use of CSS Hacks
CSS hacks are great for making your website compatible with all existing browsers but there is such thing as web standards. The majority of the time there are valid methods of doing things without the use of CSS hacks and a coder that uses CSS hacks loosely and luxuriously are most likely too lazy to spend the time to figure it out.
6. Misspelled Words / Grammar
There is no excuse to have misspelled words/grammar in websites today. A webmaster serious about his work should at least take the time to run his content through Microsoft Word or some spell check application before uploading it for all to see. Especially on the front page of the site.
7. Broken links
Sure there are times when this problem is unavoidable, but as a general rule of thumb, broken links are bad, very bad. Broken links drives people away from a website and is a very frowned upon mistake. There are many tools out there where you can scan your site for broken links -- use them.
8. HTML Editors
I tend to look at HTML editors as evil, vile, and sinful applications. Not only does it make it harder to actually learn proper coding, some HTML editors don't even validate properly. Some even output code in all uppercase, while many just make the code look ugly. I mean simple editors like Notepad++ or AceHTML are fine for using certain features (goto line, color syntax, etc), but using drag n drop and click/point features generally turn messy and don't optimize code like they should. Please note that there are some exceptions to this, but many people seem to abuse HTML editors.
9. Non-modular/SSI-based design
I've seen people who code each individual page of their site. Yes, they'll actually put the code for their layout in each of their content pages. While they may not know of modular/SSI-based design, I've personally told a few of them about it and found them not taking my advice. They'd rather be lazy in learning and code each page individually -- which in the long run, just doesn't work out too well (think re-writing 100 pages after a site redesign).
10. Site is browser/resolution dependent
When a coder designs a website and it only works in a *specific* web browser or cannot be viewed effectively without a certain resolution, it just shows they don't give a damn. Sure some may not have taken thought to checking out their site in their non-favorite web browser, but I've seen websites TELLING me I should change my resolution to view their website. Screw their website!