3D architectural renderings are important for a number of reasons:

Visualization: Renderings allow clients and other stakeholders to get a clear visual understanding of the proposed design. This can be especially useful for explaining complex design elements or for showcasing features that may not be immediately obvious from 2D drawings.
Communication: Renderings can be a powerful tool for communicating design ideas and concepts to clients, contractors, and other stakeholders. They can help to ensure that everyone is on the same page and can help to identify any potential issues or misunderstandings before construction begins.
Marketing: Renderings can be used to market a development or project to potential buyers or tenants. They can help to create excitement and generate interest in the project.
Planning: Renderings can be used to help plan and coordinate the various components of a construction project, such as materials, finishes, and fixtures. They can also be used to help plan for furniture placement and other interior design elements.