Conversion tracking is the spine

If you learn one thing properly, make it this. Modern ad platforms optimise toward the conversions you report. Report the wrong thing and the machine will very efficiently buy you more of the wrong thing, and every number in the account will look fine while doing it.

A conversion action is a definition

You choose what counts: a purchase, a lead form, a call, a signup. Each action has:

• a category (purchase, lead, signup)
• primary or secondary status — only primary actions are used for bidding
• a value, fixed or dynamic
• a counting rule — every conversion, or one per click
• a conversion window — how long after the click a conversion still counts

Counting rules matter more than they look. A lead form counted as "every" means one person submitting three times is three leads, and the algorithm will chase people who submit repeatedly.

The most common failure: optimising for the wrong depth

Form fills are easy to track and weakly related to revenue. Optimise to them and you get more form fills — including worthless ones. The fix is to feed back something closer to money: qualified lead, opportunity, closed deal, via offline conversion import from your CRM. This is the single biggest step-change available to most lead-gen accounts.

For e-commerce the equivalent is sending real values, and ideally margin rather than revenue, so the system optimises for profitable products.

Signal loss and enhanced conversions

Browser restrictions and consent requirements mean a meaningful share of conversions is never observed. Enhanced conversions send hashed first-party data — email, phone — alongside the conversion to recover matches. Where consent regimes apply, consent mode governs what is collected at all, and platforms model the gap.

The practical consequence: platform-reported conversions include modelled ones, will not reconcile exactly with your backend, and the gap varies by market.

Verify before you trust

Test the whole path end to end. Check for double counting from multiple tags. Confirm values arrive, not just events. Confirm the conversion window matches your sales cycle — a 30-day window on a 90-day sale hides most of your revenue from the algorithm.

What trips people up

• Marking everything primary. You have now told the machine a newsletter signup and a purchase are equally good.
• Never auditing tracking until something looks broken.
• Expecting platform and backend numbers to match. They will not.

You have got this when

Before optimising any campaign, you check what the primary conversion action is and whether it means what the business means by success.