diff --git a/storage/local/delta.go b/storage/local/delta.go
index 58e028159f..1ca0661840 100644
--- a/storage/local/delta.go
+++ b/storage/local/delta.go
@@ -348,6 +348,7 @@ func (acc *deltaEncodedIndexAccessor) sampleValueAtIndex(idx int) model.SampleVa
 		// No d8 for ints.
 		default:
 			acc.lastErr = fmt.Errorf("invalid number of bytes for integer delta: %d", acc.vBytes)
+			return 0
 		}
 	} else {
 		switch acc.vBytes {