Have you ever actually listened to a canary for a sustained period of time? They're actually kind of annoying, and clearly have no interest in your preferences or desires. But they were brought down into the mines anyways. They could have used pigeons, after all, pigeons were commonplace and commonly mass-farmed. But they chose canaries because they would never shut up, never take breaks, screeching every moment they can. A pigeon might die in the mines and not be noticed for a long while, too late to save yourself. A canary's absence is noted immediately.
He's a canary. It's an important role.
Have you ever actually listened to a canary for a sustained period of time? They're actually kind of annoying, and clearly have no interest in your preferences or desires. But they were brought down into the mines anyways. They could have used pigeons, after all, pigeons were commonplace and commonly mass-farmed. But they chose canaries because they would never shut up, never take breaks, screeching every moment they can. A pigeon might die in the mines and not be noticed for a long while, too late to save yourself. A canary's absence is noted immediately.