Planned Purchase Orders

What is the business usage of planned purchase order...In what type of industry & business scenarios, the planned purchased orders are used.

As per oracle, A Planned

As per oracle, A Planned purchase Order is similar to Blanket Agreement but it provides more information to the supplier, such as tentative schedules, which suppliers can use for their forecast. I never found any real life business scenario where BPA cant be used. I guess PPO was created in 11i/R12 to satisfy few Big Oracle customers...Just a guess...if not, then why oracle removed it from Fusion Application