QS stands for "Quality Score".
Quality Score is a metric used by Google Ads to measure how relevant a keyword is for a particular ad and landing page.
Google will scan the landing page for the ad and derive the quality score for that page.
Quality Score affects how high an ad will show for a given bid on the keyword concerned.
The highest Quality Score is 10, it means that the bidder will gain a similar rank for his ad even if he only bid half as much as a bidder with a QS of 5.
Whilst anyone can set up their own accounts on Google Ads, getting cost effectiveness requires knowledge and experience.
That is why paying a professional to set up Google Ads is cost effective, as having a good campaign structure and working on factors such as QS can more than double what you actually achieve out of them.
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