Bid strategies and budget bid strategies enter learning mode when any of the following types of changes occur.
Bid strategy
- New strategy: The bid strategy is new. It can take a few days after creating a new bid strategy for it to enter learning mode.
- Setting change: The specified cost per action (CPA) or return on ad spend (ROAS) target changed.
- Composition change: The bid strategy's portfolio changed. That is, campaigns (or items in the campaigns) were added or removed.
When these types of changes occur, it may take some time for the bid strategy to adjust to the new settings.
Budget bid strategy
- New strategy (new plan): The budget bid strategy is new. It will enter learning mode a few days after budget automation is enabled.
- Constraints change: A CPA, ROAS constraint is added, removed or adjusted.
- Composition change: A large number of campaigns are added or removed from the campaign group.
- Key metric or target change: The key metric or target is different from the previous performance plan. For example, the key metric and target from 15 May to 14 June is conversions (maximise conversions), but in a plan from 15 June to 14 July, the goal is conversion value (maximise conversion value).
- Conversion action or conversion goal change in the campaigns: The conversion actions are different than in the previous plan. For example, the conversion action from 15 May to 14 June is 'Leads' but in a plan from 15 June to 14 July, the conversion action is 'Purchases'.
When these types of changes occur, it may take about a week for the budget bid strategy to recalibrate. It has to learn how to set budgets, bids and bid adjustments from the performance history of all of the biddable items in its portfolio and adjust to new targets.
Bid and budget bid strategies learn from selected conversions and performance history of the biddable items and campaigns.
Recommendation: Let the strategy finish learning before making other changes or evaluating performance.
What affects the duration of the learning period?
The duration of the learning period is primarily affected by several factors:
- The number of conversions that your campaigns obtain.
- The length of a typical conversion delay or the amount of time it takes for a click to result in a conversion.
- The type of bid strategy (target CPA and target ROAS) or budget bid strategy (maximise conversions and maximise conversion value).
It can take about 2–3 conversion cycles for the bid strategy to calibrate to certain types of changes, although it can be faster depending on the amount of conversion data. Conversion data from previous campaigns can help drive faster results by speeding up the initial learning period required for bid strategy to calibrate towards your business goals. Learn how to fix the performance of your bid strategy when the conversion volume is too low.