MBO and OKR are both frameworks for goal management. MBO stands for “Management by Objectives”. The OKR model has evolved from the MBO framework. These are the main differences:
MBO defines what you want to achieve, while OKRs define the what and how.
MBO usually has annual reviews, while OKRs are evaluated every three to four months
MBO targets are private and “in silos”, while OKRs are public and transparent
MBO is linked to compensation, while this should not be the case with OKRs
MBO goals are rather conservative, while OKRs are ambitious