Design processes guide designers and design teams to thoroughly create more effective solutions. Since design is only one aspect of building a product or service, it's critical to see how design processes converge cross-functionally with business and engineering processes.
Sharing a design process fosters trust and credibility within the team while establishing a common understanding and practical expectations of what is to be tackled. Another benefit for cross-functional teams is that sharing processes builds ownership and a collaborative effort to deliver the best result instead of each person or department fending for themselves.
Whether you are a designer, engineer, marketer, or product manager, sharing and understanding a team's design process holistically benefits team members and the end product itself. Inversely, the absence of communicating how we do our best work results in the absence of trust in each other, misunderstandings of deliverables and expectations, as well as shipping a fragmented mishmash solution into the hands of users.