Why should knives be washed separately from other dishes?

The detergents used in dish-washing have chemicals and washing knives in a dishwasher can therefore shorten their lifespan and cutting edge retention.

moreover ... it can damage the other utensils as well ...

If you put knives in the sink along with other dishes you risk reaching for one of the dishes and cutting yourself. And should the dishes and knives collide it could result in broken dishes and dull knives