"ABC Logistics is planning to implement a new process to improve its warehouse operations. To ensure a smooth implementation, they are using the Process Decision Program Chart $($PDPC$)$ to anticipate potential problems and develop countermeasures."

$($a$)$ Illustrate the steps involved in developing a PDPC for ABC Logistics.

$($b$)$ Assess the effectiveness of PDPC in preventing issues during the implementation of the new warehouse process.