diff --git a/bugbear.py b/bugbear.py
index be299a4..8572908 100644
--- a/bugbear.py
+++ b/bugbear.py
@@ -1192,8 +1192,8 @@ def visit_Lambda(self, node):
 }
 B015 = Error(
     message=(
-        "B015 Pointless comparison. This comparison does nothing but waste "
-        "CPU instructions. Either prepend `assert` or remove it."
+        "B015 Result of comparison is not used. This line doesn't do"
+        "anything. Did you intend to prepend it with assert?"
     )
 )
 B016 = Error(
@@ -1213,7 +1213,8 @@ def visit_Lambda(self, node):
 )
 B018 = Error(
     message=(
-        "B018 Found useless expression. Either assign it to a variable or remove it."
+        "B018 Found useless expression. Consider either assigning it to a "
+        "variable or removing it."
     )
 )
 B019 = Error(