Does Google use a set standard for manually removing webspam?

When Google does a manual review do you guys use a “set standard” when banning (removing from the index) sites or do you guys ban based on if it “looks bad” or even smells like spam?
Billy, Sacramento

Read our quality guidelines:
http://support.google.com/webmasters/bin/answer.py?hl=en&answer=35769#3

Learn more about how Google fights spam using algorithms and manual action:
http://www.google.com/insidesearch/howsearchworks/fighting-spam.html

Have a question? Ask it in our Webmaster Help Forum: http://groups.google.com/a/googleproductforums.com/forum/#!forum/webmasters

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