Quality Score is a Google Ads diagnostic (1-10) that evaluates the quality of your ads, keywords, and landing pages compared to competitors. It is based on 3 components: expected click-through rate, ad relevance, and landing page experience. A higher Quality Score lowers your CPC and improves ad position.
A keyword with Quality Score 8/10 pays EUR 0.64 CPC for position #1. The same keyword with Quality Score 4/10 would pay EUR 1.50 for the same position — 2.3x more.