10 Common SEO Mistakes

1. Not Starting Early Enough
Even organizations that are aware of SEO's importance have a tendency to start the process too late. People in these organizations may think that SEO is about keyword selection and copywriting, but not realize that SEO also plays a critical role in technical implementation decisions. The key to remember here: it's easier to do it right the first time than to do it over.

2. Picking a Poor Content Management System
Unfortunately, many CMSs lack even basic SEO features, such as the ability to select title tags, headings, and anchor text. Other CMSs may allow these basics, but aren't crawler-friendly or create massive duplicate content.

3. Use Crawler Unfriendly Development Methods
Sometimes a senior marketing manager insists on using Flash for the whole site. Search engines are doing a better job at understanding the content within Flash files, but they still don't deal with it as well as plain HTML text. There are ways to completely block search engine spiders too, such as implementing links in JavaScript that can't be parsed by the crawler.

4. Duplicate Content Pages
There are many ways to implement duplicate content, such as creating print pages or referring to pages on the site with more than one URL (example: www.example.com and www.example.com/index.html.

5. No Canonical Redirect
Many Web sites allow http://example.com and http://www.example.com to co-exist without 301 redirecting one version of the URL to the other. This is actually a duplicate content problem, but it's so common that it deserves its own mention. A somewhat rarer cousin to this is where http://www.example.com and https://www.example.com are allowed to co-exist.

6. Pseudo Duplicate Content
One example of this is an e-commerce catalog that offers alternate sort orders for its products (e.g., a shoe catalog that allows you to sort on price, color, or size). To a user, the content on all these pages is different; to a search engine, they aren't because all the same elements of text are on the page.

7. Thin Content Pages
Many sites implement pages that have too little content per page. These can even be pages that the user sees as content rich, such as a page with images showing a product, and basic product information such as price. However, if the only text on the page that differs from other product pages is the title and heading tags and the price, the page will either be seen as a low quality page, or a duplicate.

8. Poor Use of Internal Anchor Text
A surprising number of sites still use "click here" or "more" as the anchor text on many links. This is a loss of a golden opportunity to help search engines understand what the page being linked to is about.

9. Over-Optimized Pages
Sometimes people go off the deep end after learning about SEO. They start creating overly keyword-rich pages in an effort to move their rankings upwards. This can quickly make for a poor user experience, resulting in a decrease in conversion rates and/or the site being less attractive for others to link to.
One warning signal of this is when you hear people talk about "SEO copywriting." This is a flag that the content author is thinking about search engines and not users, and that will get you into trouble. You're almost always better off having the writer focus on creating quality content, but controlling the title of the article so you can make sure that the keyword is in it.

10. Not Investing in Site Promotion
Many organizations think that the process is complete once a site is launched. They don't realize that the Web site needs to be promoted much like any other product or service. Inbound links (and in the future other references to your Web site, company, or products on the Web) are the primary voting mechanism that search engines use to tell them which are the most important sites related to a particular search query.