The Bid Multipliers are the levers that can change your final bid, and allow you to decide whether to decrease or increase your final bid in the auction based on the user search criteria at that moment. This gives you more granularity in terms of targeting your specific commercial needs and leveraging your investment as well as allowing you to optimize your returns on advertising spend in the end. Introducing the new dimensions into your bidding strategies gives you an opportunity of acquiring more valuable traffic and reduce the non-efficient costs.