Question

Why does a hurricane lessen in intensity when it hits land?

Answer 1

Because the main source of a hurricane is water. So, when it hits land there's no water nor air pressure 

Answer 2

Because then the hurricane wouldn't be able to use up fuel, water, anymore, and since water is pretty malleable and basically able to move through easy. Land, on the other hand, is hard and stiff, and difficult to move through. Basically, the difficult density affects the hurricane's movement.

I hope you like this answer, and have a good day! :D