Why are evergreens common in modern Japanese gardens?

In modern Japanese gardens, evergreens are preferred over deciduous trees because they promote a sense of simplicity, restraint, and consistency.1

Rather than seeking the gaiety, showiness, or obvious seasonal variations associated with flowering plants, designers prioritize the stable, enduring aesthetic of evergreen foliage. This choice aligns with the broader goal of creating a minimalist natural setting that inspires reflection and meditation, ensuring the garden remains a secluded, peaceful retreat throughout the year.1