The short answer
Define a small set of primary business actions, validate each event, keep campaign and referral rules clean, and compare landing-page and query evidence with accepted lead outcomes outside the analytics platform.
Define the business action first
Decide which submitted forms, calls, bookings, purchases or qualified actions matter. Separate primary outcomes from diagnostic events such as scroll or button clicks.
Create an event contract
For each event, record the trigger, required parameters, consent condition, platform destination, owner and test. Prevent the same action firing from both direct code and a tag manager.
Connect landing and query evidence
GA4 can show organic landing behaviour and configured actions. Search Console can show query, page, country and device search performance. The datasets use different definitions and should not be forced to match exactly.
Return lead quality
A submitted form is not automatically a useful lead. Add a privacy-conscious way for sales or CRM outcomes to classify accepted, rejected and progressed opportunities.
Document the limits
Consent, devices, offline conversations, attribution models and data thresholds create uncertainty. State the limit next to the decision rather than hiding it.
Primary sources used
External guidance is linked so you can check the current source and context directly.