A filter affect that Google places on new domains to stop the website from high rankings for the main keywords.
Sandbox is a phenomenon that has been claimed by people to observe in the ranking of web pages that is performed by Google. It is a so-called filter placed on new websites. Sandbox acts as a de facto (meaning: Exercising power or serving a function without being legally or officially established) probation for sites. This is done to discourage spam sites from rising quickly, getting banned and repeating the process.
Google Sandbox is very similar to a new website being placed on trial and kept lower than expected in searches. This is done prior to being given full value for its incoming links and content.
This is due to various reasons like:
There is a controversial view that the Google Sandbox exists as a separate filter from other alleged Google filters. Doubtful believe that the phenomenon merely echoes already existing Google algorithm calculations and the Sandbox effect is an illusion.
In March, 2004 website owners and search engine optimization professionals began to notice the Google Sandbox effect, real or imagined. Websites launched after those dates were noticed to not be ranking well for their first few months live on the internet. Rankings were poor despite good Google Page Ranks, strong incoming link totals and overall good optimization practices being employed.
Sites can be avoided from being kept in the Sandbox by targeting non-competitive keywords and phrases are often left out of the Sandbox as there is little point in applying the filter.
The time period of a site in Sandbox can vary from one to six months, with three to four months being the normal time frame. More competitive the keyword, the longer the site has to spend in the Sandbox. So, it is better to place less competitive keywords in the website.
The Sandbox is the best time to start adding incoming links to your site. Because of the suspected new links dampening filter, adding links while in the Sandbox solves two filters at once. Make sure to add strong keyword rich anchor text to your incoming links and vary it to include several keyword combinations.