It's important to compare clicks to sessions in Google Analytics to determine if ad clicks are generating website traffic. In my experience, search ad clicks and website sessions are closely correlated.

• Invalid clicks

Google's system automatically filters out invalid activity, such as accidental clicks or those from malicious sources, and your account is credited for them.

Unqualified clicks from an irrelevant audience can increase your account costs. To mitigate this, restrict clicks from campaigns, keywords, or ads that do not align with your key performance indicators (KPIs).

Can clicks be used as a KPI?

That’s not ideal since there may be cases where your account has received a high amount of clicks but not many website visitors. It’s best to avoid using clicks as a KPI.