Another rating system designed by Google which basically assigns a certain score determined by Google AdWords to numerous account components. The Quality score is given out on a scale of 1-10. Although the exact mechanism through which the score is decided is not explicitly revealed by Google, it is a well-known fact that the three primary factors taken into account are ad quality, relevance and landing page experience. A higher quality score directly translates to more appearances for your ad at lower bids as well as cost per click.