diff --git a/src/https.rs b/src/https.rs
index 20df354..ebdac6d 100644
--- a/src/https.rs
+++ b/src/https.rs
@@ -197,6 +197,10 @@ async fn handle_request(
 	let tags = [host_tag, method_tag.clone()];
 	metrics.requests_received.add(1, &tags);
 	metrics.requests_in_flight.add(1, &tags);
+
+	// The guard ensures that we decrement requests_in_flight in all cases where
+	// the current tasks ends, including the case where it gets canceled and
+	// doesn't run to completion (which may happen e.g. if it timeouts).
 	let _guard = InFlightGuard {
 		metrics: Arc::clone(&metrics),
 		tags: &tags,