Enter the Poet - Not Getting The Pun

I can't truly say what would make me happy, but I can tell you what makes me sad.

I can't tell you what is universally good, but I can always express the globally bad.

I can't cook a meal you're sure to like, but it's easy to create one you'd hate.

I'd never know where you would prefer to be, but could send you somewhere desolate.

Without much effort, the negative thing is the easiest to achieve.