Colour contrast between text and background is important on web pages. It affects some people’s ability to perceive the information (in other words to be able to receive the information visually).
Accessibility
Colour Contrast - Why Does It Matter? — GOV.UK
Knowledge
Information Architecture (4 Parts) — UX Knowledge Base Sketches
Information Architects are the Architects of Understanding. They “help users to understand where they are, what they’ve found, what to expect, and what’s around.”
Information Architecture
Information Architecture (4 Parts) — UX Knowledge Base Sketches