Your landing page can sell the promise and still lose the payment.
A page that converts the click is only half the job. If the checkout shows the wrong payment methods, no local option for the buyer's country, or a fulfillment claim the page made but the checkout cannot back up, the buyer hesitates at the one screen where hesitation costs you the order.
The leak is rarely the headline.
It is the gap between what the page promised and what the checkout delivers.
This is why checkout cannot be treated as the last page of the funnel. In Tagada, checkout is part of the offer system: the Checkout Builder, Payment Flows, and per-checkout payment methods exist to match the buyer you just convinced, down to the networks and local options shown.
Match the checkout to the promise, or you keep paying for traffic that bails on the last step.