diff --git a/core/engine.go b/core/engine.go
index a0c3d651f90..77488ee69d2 100644
--- a/core/engine.go
+++ b/core/engine.go
@@ -153,6 +153,16 @@ func (e *Engine) initSubMetricsAndThresholds() error {
 
 		metric.Thresholds = thresholds
 		e.metricsWithThresholds = append(e.metricsWithThresholds, metric)
+
+		// Mark the metric (and the parent metricq, if we're dealing with a
+		// submetric) as observed, so they are shown in the end-of-test summary,
+		// even if they don't have any metric samples during the test run
+		metric.Observed = true
+		e.Metrics[metric.Name] = metric
+		if metric.Sub != nil {
+			metric.Sub.Metric.Observed = true
+			e.Metrics[metric.Sub.Metric.Name] = metric.Sub.Metric
+		}
 	}
 
 	// TODO: refactor out of here when https://github.com/grafana/k6/issues/1321
@@ -439,7 +449,7 @@ func (e *Engine) processThresholds() (shouldAbort bool) {
 	t := e.executionState.GetCurrentTestRunDuration()
 
 	e.thresholdsTainted = false
-	for _, m := range e.Metrics {
+	for _, m := range e.metricsWithThresholds {
 		if len(m.Thresholds.Thresholds) == 0 {
 			continue
 		}
diff --git a/core/engine_test.go b/core/engine_test.go
index eb20cba88fa..c3aac19c467 100644
--- a/core/engine_test.go
+++ b/core/engine_test.go
@@ -395,7 +395,12 @@ func TestEngine_processThresholds(t *testing.T) {
 		"submetric,match,passing":   {true, map[string][]string{"my_metric{a:1}": {"value<2"}}, false},
 		"submetric,match,failing":   {false, map[string][]string{"my_metric{a:1}": {"value>1.25"}}, false},
 		"submetric,nomatch,passing": {true, map[string][]string{"my_metric{a:2}": {"value<2"}}, false},
-		"submetric,nomatch,failing": {true, map[string][]string{"my_metric{a:2}": {"value>1.25"}}, false},
+		"submetric,nomatch,failing": {false, map[string][]string{"my_metric{a:2}": {"value>1.25"}}, false},
+
+		"unused,passing":      {true, map[string][]string{"unused_counter": {"count==0"}}, false},
+		"unused,failing":      {false, map[string][]string{"unused_counter": {"count>1"}}, false},
+		"unused,subm,passing": {true, map[string][]string{"unused_counter{a:2}": {"count<1"}}, false},
+		"unused,subm,failing": {false, map[string][]string{"unused_counter{a:2}": {"count>1"}}, false},
 	}
 
 	for name, data := range testdata {
@@ -406,6 +411,8 @@ func TestEngine_processThresholds(t *testing.T) {
 			registry := metrics.NewRegistry()
 			metric, err := registry.NewMetric("my_metric", stats.Gauge)
 			require.NoError(t, err)
+			_, err = registry.NewMetric("unused_counter", stats.Counter)
+			require.NoError(t, err)
 
 			thresholds := make(map[string]stats.Thresholds, len(data.ths))
 			for m, srcs := range data.ths {