In the old days - Oh Gosh when we start saying this, it is not a good sign... Mmm, let's start over! Since its creation, Google had only one goal - "serve" you the best result page. The quality of a website is hard to put into numbers and into ranking... So, some time ago, Google was working very hard to create the most effective algorithm. Google people created one algorithm, tried it for some times then realized it sucked. They were then ready to change to the next one. Few tweaks on the formula and your website was jumping from 100 on Monday, 20 on Tuesday and 80 on Wednesday... By the time, all of your website was crawled and indexed with the new algorithm, your URL was finally reaching a stable point. All algorithms have weaknesses and Google people were always running after THE BEST SOLUTION. The Google was Rock and Rolling, so does the ranking! Finally, Google found find an algorithm enough satisfying they could stick to it and finally tune the engine. Google was Slowing, the ranking was not suffering much from the tuning. SEO guys were at peace! Two years ago, Google finally sent his white and black ambassador, PANDA, to check things out, then they sent his assistant, PENGUIN. The mammal and the bird have two different schedule and kick ranking once a while. The dance started again - or shall i say the dances, one from Asia, one from Antarctica! These updates add-ons are simply resetting the Internet. The solution? Follow the guidelines to the letter and take good care of your website and your visitors!