diff --git a/dan/post_processing.py b/dan/post_processing.py
index e2fdca5623e66caa534b0726b2df89546143b0cf..180d021fd651dd678afc5a65ae450dcc854785b6 100644
--- a/dan/post_processing.py
+++ b/dan/post_processing.py
@@ -15,7 +15,6 @@ class PostProcessingModule:
     def __init__(self):
         self.prediction = None
         self.confidence = None
-        self.num_op = 0
 
     def post_processing(self):
         raise NotImplementedError
@@ -39,7 +38,6 @@ class PostProcessingModule:
         self.prediction.insert(index, label)
         if self.confidence is not None:
             self.confidence.insert(index, 0)
-        self.num_op += 1
 
     def del_label(self, index):
         """
@@ -48,7 +46,6 @@ class PostProcessingModule:
         del self.prediction[index]
         if self.confidence is not None:
             del self.confidence[index]
-        self.num_op += 1
 
 
 class PostProcessingModuleSIMARA(PostProcessingModule):