When you can dance on any music or stage then why don't Google. LOL anyway, it is a effect when Google update something new.
In google dancing keywords rank not satiable in google. Day day change keywords possition in google. It my think If you have other think Please share with me.
Google Dance is an out-dated slang term used to describe the period of time in which Google used to rebuild its rankings, and as a result of this rebuilding, rankings of Web sites on Google's SERP may fluctuate in order during a several day period. The "Google Dance" would happen anywhere up to 36 times per year, however in 2003 Google begun updating its index on a weekly basis, which all but eliminated the Google Dance.
It is nothing but when Google updates rank then fluctuation may happen to sites which is called "Google Dance". The term is not using now-a-days. It is called "rebuild" currently.