Some people will try anything to get first page listings in the major search engines. Unfortunately there are many companies that promise high search rankings, the vast majority of which are merely spam.

Spam for search engines includes: automatic doorway pages (not to be confused with legitimate landing pages), cloaking and false redirect codes, keyword stuffing, hidden text or links, and automated listing systems. The major search engines, especially Google, will penalize sites by either dropping the ranking of the website or removing the site from the search engine database completely.

While Google may eventually forgive and lift the penalization it is not a quick process to get back to the top. Often that process can take a year or more as Google learns to trust the site once again.

Moral of the story - don't participate in "black" search engine optimization techiques. Ask questions about how the SEO is performed and if you are not comfortable with the methods used, look for another company.