diff --git a/src/babel/transformation/transformers/playground/memoization-operator.js b/src/babel/transformation/transformers/playground/memoization-operator.js
index 7c63ad102a..f8d55d854c 100644
--- a/src/babel/transformation/transformers/playground/memoization-operator.js
+++ b/src/babel/transformation/transformers/playground/memoization-operator.js
@@ -11,6 +11,7 @@ build(exports, {
   },
 
   build(node, file) {
+    console.error("The memoization operator is deprecated and will be removed in 5.0.0");
     return t.unaryExpression(
       "!",
       t.callExpression(
diff --git a/src/babel/transformation/transformers/playground/object-getter-memoization.js b/src/babel/transformation/transformers/playground/object-getter-memoization.js
index af5ffe8c4c..e2f0ac6487 100644
--- a/src/babel/transformation/transformers/playground/object-getter-memoization.js
+++ b/src/babel/transformation/transformers/playground/object-getter-memoization.js
@@ -20,6 +20,8 @@ export function MethodDefinition(node, parent, scope, file) {
   if (node.kind !== "memo") return;
   node.kind = "get";
 
+  console.error("Object getter memoization is deprecated and will be removed in 5.0.0");
+
   var value = node.value;
   t.ensureBlock(value);