Reference: https://www.bmc.com/blogs/itil-service-level-management/

Value Streams & Processes
The value streams and processes dimension is concerned with how the various parts of the organization work in an integrated and coordinated way to enable value creation through products and services. This dimension defines the activities, workflows, controls and procedures needed to achieve agreed objectives. What matters in service management is that an organization establishes an operating model that that effectively organizes the key activities needed to manage products and services.
Value streams
A value stream is defined as a series of steps an organization undertakes to create and deliver products and services to consumers.
Structuring the organization's service and product portfolios around value streams allows it to have a clear picture of what it delivers and how, and to make continual improvements to its services. By mapping its value streams, an organization can identify what is critical, what introduces waste and what can be improved upon.
Processes
A process is defined as a set of interrelated or interacting activities that transform inputs into outputs.
Processes define the sequence of actions and their dependencies, as well as describe what is done to accomplish an objective. Processes are underpinned by policies and can be broken down further through procedures which outline what is done, when, and by whom.
https://www.bmc.com/blogs/itil-four-dimensions-service-management/

Explanation
Value streams and processes focus mainly on those areas which ensure integration and coordination of various actions and parts which contribute towards better value creation for the organization. This dimension is more concerned about the way the organization has organized the activities or processes and how it enables and ensures the value creation across all stakeholders.
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