Jane is making adjustments to her cost per action (CPA) target every day and is frustrated that DoubleClick Search seems to always be calibrating. Why does this keep happening to Jane?

DoubleClick Search (DS) employs a calibration period after significant CPA target changes to ensure its bidding algorithms can accurately learn and adapt to the new goal. This period allows DS to gather sufficient data under the new conditions to optimize performance effectively. Frequent, large adjustments to the CPA target restart or prolong this calibration, preventing the system from stabilizing and reaching optimal performance. The other options are less accurate: While a high CPA might indicate inefficiency, it doesn't directly explain continuous calibration due to daily target changes. Insufficient conversion volume can hinder optimization, but the primary reason for continuous calibration after daily adjustments is the system's need to learn from those changes. Insufficient budget for ROI goals is a separate issue that might impact performance but isn't the direct cause of the calibration period itself.