add_action('after_setup_theme', 'remove_admin_bar');
function remove_admin_bar() {
    if (!current_user_can('administrator') && !is_admin()) {
        show_admin_bar(false);
    }
}

Case Studies: Why Disable the Admin Bar for Non-Administrators?

Case Study 1: Improved User Experience for Subscribers

Scenario:
A WordPress site focuses on content consumption, such as a blog or an online magazine, with a large number of subscribers who do not need access to the backend.

Reason:
Disabling the admin bar for subscribers (or any non-admin users) improves the user experience by providing a cleaner interface without unnecessary options. This is particularly useful for users who are only interested in reading content and have no reason to interact with the WordPress backend.

Outcome:
Subscribers enjoy a more streamlined and less cluttered experience, leading to increased satisfaction and potentially higher engagement rates with the site’s content.

Case Study 2: Enhanced Security for eCommerce Sites

Scenario:
An eCommerce website using WooCommerce has customers who register accounts for purchasing products and tracking orders.

Reason:
Disabling the admin bar for non-admin users can reduce the risk of accidental access to backend features or settings. It also minimizes the chances of customers seeing or interacting with elements that could potentially lead to security vulnerabilities if mishandled.

Outcome:
The site’s security is enhanced as customers are only provided with the necessary front-end features. This ensures they have a smooth shopping experience while the site’s backend remains protected from unauthorized access.

Summary

By following the instructions above and understanding the practical reasons through these case studies, you can effectively disable the WordPress admin bar for all users except administrators, enhancing both user experience and site security.