If you ask company employees about where their products reside, the answer will often be "in the ERP system".
In many cases this make sense, but it would be a big advantage to many companies to let their products "play in the sandbox" until they are mature enough to move into the ERP system.
"Sandbox" in this context means a PIM system, one designed to handle all types of product information. The idea of letting the products' life cycle start in the PIM system is to keep the ERP system as "clean" as possible.