diff --git a/src/crested/tl/_crested.py b/src/crested/tl/_crested.py
index 687dbcb..7444ebf 100644
--- a/src/crested/tl/_crested.py
+++ b/src/crested/tl/_crested.py
@@ -1462,6 +1462,9 @@ def enhancer_design_motif_implementation(
                     }
                 )
 
+            if preserve_inserted_motifs:
+                inserted_motif_locations = np.array([])
+
             # sequentially insert motifs
             for pattern_name in patterns:
                 number_of_insertions = insertions_per_pattern[pattern_name]