diff --git a/pyproject_buildrequires.py b/pyproject_buildrequires.py
index e91111f..515da95 100644
--- a/pyproject_buildrequires.py
+++ b/pyproject_buildrequires.py
@@ -248,6 +248,14 @@ def get_backend(requirements):
         # with pyproject.toml without a specified build backend.
         # If the default requirements change, also change them in the macro!
         requirements.add('setuptools >= 40.8', source='default build backend')
+        # PEP 517 doesn't mandate depending on wheel when the default backend is used.
+        # Historically, it used to be assumed as necessary, but later it turned out to be wrong.
+        # See the removal in pip and build:
+        #   https://github.com/pypa/pip/pull/12449
+        #   https://github.com/pypa/build/pull/716
+        # However, the requirement *will* be generated by setuptools anyway
+        # as part of get_requires_for_build_wheel().
+        # So we might as well keep it to skip one redundant step.
         requirements.add('wheel', source='default build backend')
 
     requirements.check(source='build backend')