Reasons for Decreasing Google Page Rank:

[shruchi nagar]

The SEO experts all over the web have been battering their gums about the massive effects that update has made to rankings and pointing to all sorts of dramatic changes that they feel have been made to the algorithm.
The sites that are being badly affected have been using techniques such as:
• Doorway pages
• Hidden text
• Multiple domains
• Buying links
• Accepting off-focus reciprocal links from other sites
• Working with link farms and link exchange schemes
• Using various cloaking techniques
• Using duplicate content on different domain names
If your rankings on Google fell over the last month, you website has probably been affected by this ranking algorithm change.
Change in the Google ranking algorithm
Google wants to make its search engine results pages more relevant by removing some of the spam. It seems that the following elements are the most common reasons if your Google rankings dropped:
• hidden text on your web pages (especially text that is hidden in invisible CSS layers)
• paid links or other links that are considered outside of Google’s quality guidelines
• overuse of internal links or anchor text as the sole source of optimization
What if website ranking have dropped?
If you were guilty of any of the above, and you lost positions, stop doing it, apologize to Google and ask them to have another look at your site, once all the black hat techniques have been removed from your site.
• If you use CSS on your web pages, search for style sheets that might be interpreted as spam attempts.
• Make sure that you have links from the right web sites. While it is not important that if a link is a reciprocal link or not, it is very important that the links are from related sites.
• Do not overuse the same keyword in links to your web site. Use different keywords so that the links to your website look natural.
If your web site rankings on Google have dropped, don’t panic and follow the tips above. Chances are good that you’ll get your high rankings back.

[therence]

^ consider also the Keyword Ranking issue. Are Google Keyserp tool reliable?

[Ka-canor]

That technique will hurt or may banned your site to major search engine.

[rayter]

Pretty good summary! The bottom line is, be ethical and you'll be successful in your SEO campaign.

[nsagent]

The only thing I can think of that reduces PR is less links or links from lower PR pages.

[KrazyG]

Losing lots of IBLs will definitely get your PR down.

[vitebseo]

I think its very important for a website or a blog to maintain an updated, fresh content all the time to ensure that the PR doesn't falls.

[Roger_Silvester]

Some very nice tips explained here. Thanks for the share.

Well in my opinion, anything that goes against the Google Webmasters Guidelines will result in the decrease in the Page Rank of a site.

[JobsWages]

"apologize to Google and ask them to have another look at your site"

Can you actually "Ask Google For Another Look"?
I thought you just had to wait!

[janicejan]

those will surely degrade your page ranking and google might also penalized your site by doing it.. thanks for the info, I'll keep them in mind.

[cliff1114]

very usefull,
build many backlinks in a few time also casuse it

[myndconsulting]

It's better to follow google webmaster guidelines to increase the chance of getting a high page rank...

[jessy100]

if there is duplicate content in your site. then page rank will decrease....

http://www.schoolofseointernational.com

[foodsnark]

Thank for a information.

[tata1310]

Paid Review can also the culprit of your PR's drop. The line between Paid Review and Links Ads become blur now