diff --git a/src/lib.rs b/src/lib.rs
index 37c3b1f41..4acbbe112 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2299,6 +2299,7 @@ pub trait Itertools: Iterator {
 
     /// `.collect_vec()` is simply a type specialization of [`Iterator::collect`],
     /// for convenience.
+    #[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"]
     #[cfg(feature = "use_alloc")]
     fn collect_vec(self) -> Vec<Self::Item>
     where
@@ -2330,6 +2331,7 @@ pub trait Itertools: Iterator {
     ///
     /// # let _ = do_stuff;
     /// ```
+    #[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"]
     fn try_collect<T, U, E>(self) -> Result<U, E>
     where
         Self: Sized + Iterator<Item = Result<T, E>>,