We run display campaigns on manual bidding before migrating them onto automated bidding. Automated bidding works better when there is a baseline of campaign metrics to extract bidding signals from.
We find that automated bidding machine learning works better if before using it, a baseline of performance metrics exists. The baseline of campaign metrics also allows us to compare manually bidding performance with automated bidding performance.
Regardless of the type of bidding, new display campaigns usually take a bit of time to develop a stable serving pattern after launch. Typically this is just a few days, but it varies depending upon the scale of the campaign, and the market targeted.
Typically campaigns will be ready to transition to automated bidding within 2 to 6 weeks after launch.