diff --git a/README.md b/README.md
index 86d1cd0..c3c1e05 100644
--- a/README.md
+++ b/README.md
@@ -56,7 +56,7 @@
 	// simulating some work
 	max := 100 * time.Millisecond
 	for i := 0; i < total; i++ {
-		bar.StartBlock()
+		bar.StartBlock() // optional call, required for ETA
 		time.Sleep(time.Duration(rand.Intn(10)+1) * max / 10)
 		// increment by 1 (there is bar.IncrBy(int) method, if needed)
 		bar.Increment()
diff --git a/examples/singleBar/main.go b/examples/singleBar/main.go
index e32266a..7876002 100644
--- a/examples/singleBar/main.go
+++ b/examples/singleBar/main.go
@@ -37,7 +37,7 @@
 	// simulating some work
 	max := 100 * time.Millisecond
 	for i := 0; i < total; i++ {
-		bar.StartBlock()
+		bar.StartBlock() // optional call, required for ETA
 		time.Sleep(time.Duration(rand.Intn(10)+1) * max / 10)
 		// Increment by 1 (there is bar.IncrBy(int) method, if needed)
 		bar.Increment()