diff --git a/progress.go b/progress.go
index 953827f..dbf868e 100644
--- a/progress.go
+++ b/progress.go
@@ -341,6 +341,7 @@
 		b := heap.Pop(&s.bHeap).(*Bar)
 		frame := <-b.frameCh
 		if frame.err != nil {
+			// b.frameCh is buffered it's ok to return here
 			return frame.err
 		}
 		var usedRows int