eli5: How is burning waste less harmful than letting nature decompose of it?

Question

I understand that certain substances such as sodium hydroxide, acetone, batterys, plastic and even aluminum are harmful but trash is already being separated quite well in first world countries. So how is burning biological waste more effective? Or is it just easier?

I seek an actual explanation, not yes/no.

Thanks for your knowledge in advance.

In: 5

Answer 1

At our current set up most land fills are not set up to decompose, just store. Yes there is some decomp but not at any decent rate.