diff --git a/rclcpp/include/rclcpp/executors.hpp b/rclcpp/include/rclcpp/executors.hpp
index cc965ef..ff3b463 100644
--- a/rclcpp/include/rclcpp/executors.hpp
+++ b/rclcpp/include/rclcpp/executors.hpp
@@ -36,6 +36,8 @@ spin_node_until_future_complete(
   std::shared_future<FutureT> & future)
 {
   std::future_status status;
+  // TODO: does not work recursively right, can't call spin_node_until_future_complete
+  // inside a callback executed by an executor.
   do {
     executor.spin_node_some(node_ptr);
     status = future.wait_for(std::chrono::seconds(0));