When is black burned?
This is a good question about differentiating between burned and 'browned', if you will.

Browning meat, which is often searing, is a way to introduce great flavors from the Maillard reaction, is the holy grail of meat cookery.

There are other techniques, such as 'Blackening' which provide a very spicy sear to food, but that is a different animal.

In essence, the answer to your question is 'Does it meet the criteria you are going for?

Braised short ribs are browned, often hard.

Brisket is smoked for a loooooong time, and get a big smoky, burny flavor?

Ultimately, is the effect unpleasant?

Blackened catfish, a filet of fish seared under high heat in certain spices is a prize dish,but not 'burnt.'

Does the technique want the char flavor?

If no, then burnt = not good.