diff --git a/datafusion/physical-expr-common/src/physical_expr.rs b/datafusion/physical-expr-common/src/physical_expr.rs
index 492383663d45..e8280409c027 100644
--- a/datafusion/physical-expr-common/src/physical_expr.rs
+++ b/datafusion/physical-expr-common/src/physical_expr.rs
@@ -565,9 +565,8 @@ pub fn fmt_sql(expr: &dyn PhysicalExpr) -> impl Display + '_ {
 ///
 /// # Returns
 ///
-/// Returns an `Option<Arc<dyn PhysicalExpr>>` which is the snapshot of the
-/// `PhysicalExpr` if it is dynamic. If the `PhysicalExpr` does not have
-/// any dynamic references or state, it returns `None`.
+/// Returns a snapshot of the `PhysicalExpr` if it is dynamic, otherwise
+/// returns itself.
 pub fn snapshot_physical_expr(
     expr: Arc<dyn PhysicalExpr>,
 ) -> Result<Arc<dyn PhysicalExpr>> {