Model and Form

Hello,

I'm new user of MVC and I have a few questions regarding Models.

If you read this tutorial you can see

Model

PHP Code:

public function set_news()
{
    $this->load->helper('url');

    $slug = url_title($this->input->post('title'), 'dash', TRUE);

    $data = array(
        'title' => $this->input->post('title'),
        'slug' => $slug,
        'text' => $this->input->post('text')
    );

    return $this->db->insert('news', $data);
} 


Why is it better to read inputs from Forms into Models rather than into Controllers ?
Is it not "more MVC" to read inputs from Forms into Controllers ?

Like this
Controller

PHP Code:

public function create()
{
    ...
    $this->load->helper('url');

    $slug = url_title($this->input->post('title'), 'dash', TRUE);

    $data = array(
        'title' => $this->input->post('title'),
        'slug' => $slug,
        'text' => $this->input->post('text')
    );

   $this->news_model->set_news($data);
} 


Model

PHP Code:

public function set_news($data)
{
    return $this->db->insert('news', $data);
} 


Thanks for your help !