Infinite counting in WordPress

This looks like a custom function.

It’s passing $count to a function called array_pick() to limit the size of your follower array. It also looks like array_pick() is a custom function.

But you can easily stop the function from limiting your count by removing the call to array_pick():

function get_random_followers($userid, $count = 10){

    $followers = get_the_author_meta('followers', $userid);

    /** if no followers at the moment */
    if( !is_array($followers)){
        $return = "";
    } else {

        $return = '<ul class="widget_follow">' . "\n";
        foreach( $followers as $folow){

            $return .= "<li>";
                $return .= '<a href="' . get_author_posts_url($folow) . '" title="' . get_the_author_meta('display_name', $folow) . '">';
                    if( get_the_author_meta( 'user_custom_avatar', $folow ) != "" ) {
                        $return .= '<img src="' . get_the_author_meta( 'user_custom_avatar', $folow ) . '" alt="" />';
                    } else {
                        $return .= get_avatar( get_the_author_meta( 'user_email', $folow ), '40' );
                    }
                $return .= '</a>';
            $return .= "<li>";

        }
        $return .= '</ul>' . "\n";
    }

    echo $return;

}

Instead of turning $followers into a 10-item subset ($flw in your example), we loop through the entire $followers collection.