If a campaign objective is 'website conversions' and the bidding strategy is 'target cost', what data input is absolutely required for X's algorithm to function correctly?

If the campaign objective is 'website conversions' and the bidding strategy is 'target cost', conversion tracking data, specifically a properly configured X Pixel or Conversions API, is absolutely required for X's algorithm to function correctly. 'Website conversions' means you want users who click your X ad to complete a specific action on your website, such as a purchase, form submission, or signup. 'Target cost' bidding tells X to automatically optimize your bids to achieve a desired cost per conversion. Without conversion tracking, X has no way to know when a user who clicked on your ad actually completed the desired action on your website. The X Pixel or Conversions API tracks these actions and sends the data back to X, allowing the algorithm to learn which users and ad placements are most likely to drive conversions at your target cost. Without this data, the algorithm cannot optimize effectively, resulting in wasted ad spend and a failure to achieve your conversion goals. For example, without conversion tracking, X might optimize for clicks, which are easily achieved but don't necessarily translate into actual purchases on your website.