diff --git a/README.md b/README.md
index 57433ebb1..e8088ff33 100644
--- a/README.md
+++ b/README.md
@@ -512,7 +512,7 @@ Use array destructuring to swap values between two variables.
 
 ### Tail of list
 
-Return `arr.slice(1)`.
+Return `arr.slice(1)` if the array's `length` is more than `1`, otherwise return the whole array.
 
 ```js
 const tail = arr => arr.length > 1 ? arr.slice(1) : arr;
diff --git a/snippets/tail-of-list.md b/snippets/tail-of-list.md
index cecca8e8e..d0c9681c3 100644
--- a/snippets/tail-of-list.md
+++ b/snippets/tail-of-list.md
@@ -1,6 +1,6 @@
 ### Tail of list
 
-Return `arr.slice(1)`.
+Return `arr.slice(1)` if the array's `length` is more than `1`, otherwise return the whole array.
 
 ```js
 const tail = arr => arr.length > 1 ? arr.slice(1) : arr;