diff --git a/src/wp-includes/author-template.php b/src/wp-includes/author-template.php
index 2570a4035b..faeb6a89a0 100644
--- a/src/wp-includes/author-template.php
+++ b/src/wp-includes/author-template.php
@@ -481,14 +481,15 @@ function wp_list_authors( $args = '' ) {
 	$post_counts = apply_filters( 'pre_wp_list_authors_post_counts_query', false, $parsed_args );
 
 	if ( ! is_array( $post_counts ) ) {
-		$post_counts = $wpdb->get_results(
+		$post_counts       = array();
+		$post_counts_query = $wpdb->get_results(
 			"SELECT DISTINCT post_author, COUNT(ID) AS count
 			FROM $wpdb->posts
 			WHERE " . get_private_posts_cap_sql( 'post' ) . '
 			GROUP BY post_author'
 		);
 
-		foreach ( (array) $post_counts as $row ) {
+		foreach ( (array) $post_counts_query as $row ) {
 			$post_counts[ $row->post_author ] = $row->count;
 		}
 	}
diff --git a/tests/phpunit/tests/user/wpListAuthors.php b/tests/phpunit/tests/user/wpListAuthors.php
index ebf557157a..90a22e39d9 100644
--- a/tests/phpunit/tests/user/wpListAuthors.php
+++ b/tests/phpunit/tests/user/wpListAuthors.php
@@ -146,6 +146,31 @@ class Tests_User_wpListAuthors extends WP_UnitTestCase {
 		);
 	}
 
+	/**
+	 * Ensures the 'optioncount' parameter does not throw an error when there are authors without posts.
+	 *
+	 * @ticket 57011
+	 */
+	public function test_wp_list_authors_optioncount_should_not_error_for_empty_authors() {
+		/*
+		 * The main purpose of this test is to ensure that the error below is not thrown:
+		 *
+		 * Error: Object of class stdClass could not be converted to string
+		 *
+		 * In place of direct testing we ensure `wp_list_authors()` returns a list of authors
+		 * at least one of which is empty.
+		 */
+		$actual = wp_list_authors(
+			array(
+				'optioncount'   => true,
+				'hide_empty'    => false,
+				'exclude_admin' => false,
+				'echo'          => false,
+			)
+		);
+		$this->assertStringContainsString( '(0)', $actual );
+	}
+
 	public function test_wp_list_authors_exclude_admin() {
 		self::factory()->post->create(
 			array(