Correct statement is that all deserts are not hot at daytime.
Explanation:
Actually desert is any area or piece of land with no fertility for plants and hostile for living population.
As in living areas of world, there are some highly hoot ares with no water and precipitation. So these areas are known to be deserts like Cholistan, Sahara etc.
But in this world there are also some ares which have temperature to minus degrees. Which is also uninhabited place.
These are also deserts known as cold deserts.
Antarctica is the greatest cold desert of the world.
