Which Google Ads metrics matter the most for campaign success: CTR, CPC, CPA, or ROAS?

I’m trying to understand which metrics actually define the success of a Google Ads campaign. I know the basics: CTR (Click-Through Rate) measures engagement CPC (Cost Per Click) measures cost efficiency CPA (Cost Per Acquisition) measures conversion cost ROAS (Return on Ad Spend) measures profitability But I’m confused about: Which metric should be prioritized in real campaigns? Is a high CTR always good, or can it be misleading? How do you balance CPC and CPA when scaling campaigns? In what scenarios is ROAS the most important metric? Would love to hear practical insights from people managing real ad budgets.