Why does plastic chopping boards blunt knives?

Plastic chopping boards can blunt knives because the material is softer than the steel of the knife blade, which can cause the edge to deform over time. The repeated impact and friction from cutting can lead to micro-chipping or dulling of the blade. Additionally, some plastic boards can have a textured surface that may exacerbate this dulling effect. Overall, while plastic boards are gentler than harder surfaces, they can still contribute to knife wear.