Laravel Middleware以不正确的顺序执行

I have a Middleware for ajax-only routes.

// AjaxOnly Middleware class
public function handle($request, Closure $next)
{
    if (!$request->ajax()) {
        // dd('I\'m (condition) working as expected!');
        return response()->view('layouts.app');
    }

    dd('I never work!');

    return $next($request);
}

Here is my routes web.php

// Ajax only routes
Route::group(['middleware' => 'ajaxOnly'], function () {

    // Work an print 'false'
    // dd(Request::ajax());

    // Redirect me to /login page
    Route::group(['middleware' => ['auth:user']], function () {

        Route::get('/', 'HomeController@index')->name('home');
    });

    // Authentication routes
    Auth::routes();
});

So, can someone explain why the code continues to run inside Middleware-protected closure? Thanks.

UPD: Just clarify -

1. Expected behavior: layouts.app in my browser.
2. Real behavior: redirect to login page.

You can adjust your middleware priority to ensure the correct middleware executes in the correct order. You can achieve this by overriding the default $middlewarePriority in your Kernel.php file.

/**
 * The priority-sorted list of middleware.
 *
 * Forces the listed middleware to always be in the given order.
 *
 * @var array
 */
protected $middlewarePriority = [
    \Illuminate\xxx\Middleware\AjaxOnly::class,
    \Illuminate\xxx\Middleware\Auth::class,
];

You can follow what Illuminate\Routing\Router does with $middlewarePriorty here in the source code.