diff --git a/model_data/recommendations/WallRecommendations.py b/model_data/recommendations/WallRecommendations.py
index 347b7e20..7c7e3bb9 100644
--- a/model_data/recommendations/WallRecommendations.py
+++ b/model_data/recommendations/WallRecommendations.py
@@ -426,7 +426,7 @@ class WallRecommendations(BaseUtility):
         not_diminishing_return = [
             rec for rec in self.recommendations if rec["new_u_value"] >= self.DIMINISHING_RETURNS_U_VALUE
         ]
-        if not not_diminishing_return:
+        if not_diminishing_return:
             self.recommendations = [
                 rec for rec in self.recommendations if rec["new_u_value"] >= self.DIMINISHING_RETURNS_U_VALUE
             ]