diff --git a/benchmark/benchmark.py b/benchmark/benchmark.py
index ca6d263a8..c713a94f8 100755
--- a/benchmark/benchmark.py
+++ b/benchmark/benchmark.py
@@ -289,6 +289,7 @@ def main(
         dirname.rename(dest)
 
     if not dirname.exists():
+        # only copy the practice subdirs with the exercises ai!
         print(f"Copying {original_dname} -> {dirname} ...")
         shutil.copytree(original_dname, dirname)
         print("...done")