What is the sandbox effect?

What is the sandbox effect?

so certainly, these filters must certainly have a sensitivity inversely proportional to the age of the domain, but I do not believe that the age of a domain is sufficient to protect us from this filter ... I am therefore convinced that the effect "SandBox" can also apply to the old domains , I have experienced with an old domain (5 years) out of "penalty" these days (after 6 months to the day) and found all these previous places!

Sandbox effect is a filter that Google applies to new websites that want to rank in the search results for specific phrases. The filter exists to prevent SEOs and spammers from easily manipulating search results by satisfying all of Google’s major offsite and onsite factors.

The Google Sandbox Effect is a theory used to explain why newly-registered domains or domains with frequent ownership changes rank poorly in Google Search Engine Results Pages (SERPS). In other words new websites are put into a �sandbox� or a holding area and have their search ratings on hold until they can prove worthy of ranking.