It's search engine's responsibility to worry about people seeking relevant information online. To produce best possible search results, Google takes different approaches and consistently update their search algorithm. While online searchers benefit from improved search experience, online publishers have to put more effort on adopting with updated search algorithms. Not if you were following good SEO practices though.
Are you familiar with Google's Webmaster Guidelines? You MUST. Especially the quality guidelines. If you have been violating any of stated guidelines, Google reserve the right to demote or remove your pages from Google search results.
In case if Google found your site has been violating webmaster guidelines, or involved with bad practices or posing a threat online, sooner or later, you will find your site performs poorly than it used to be. It's not only your actions, but also external factors can affect on poor search ranking too. For example, low quality backlinks is one of those factors you need to keep monitoring.
Most of the processes behind Google search are automated. If Googlebots found your site contains malware, your pages will automatically demoted or removed from search results. But yet, automated processes may not very effective in every scenario. Therefore, Google may take manual actions to improve the search quality and such actions will directly affect search ranking too.
Now you don't need to wait for a confirmation email at all. It's more transparent and you can simply know about any manual actions via Google Webmaster Tools.
However, your new rankings may not be the same as earlier as there are different signals being affected on how pages rank on Google search.
Let's take a look at how to send a reconsideration request.
Before You Go:
2. Now select relevant blog or website from the drop down menu.
5. If you couldn't find any manual actions, you don't need to file a reconsideration request. You can't either. Else, you can find corresponding reasons along with affected URLs.
6. Now take the addressed problems into account and fix them. You will also find helpful links listed there on how to resolve each issue too.
7. As you fix each issue, you can click Request a Review button corresponding to each match to ask Google to reconsider your site and pages.