Getting error when calling connect as function in prepare statement - php

Question

EDIT. My error ONLY occurs when calling database connection as a function, if I call my database connection normally, the error do not occur.
I'm trying to execute a prepare statement with database connection as a function so that it can be reused inside other functions. Executing normal SQL codes work when using database connection function but I'm getting errors when I try to use in a prepare statement.
This is my code.
function connect(){
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "test";
$conn = new mysqli($servername, $username, $password, $dbname);
return $conn;
}
if (connect()->connect_error) {
die("Connection failed: " . connect()->connect_error);
} else {
echo "GOOD";
}
$val = "1";
$stmt = connect()->prepare("SELECT * FROM countries WHERE id = ?");
$stmt->bind_param("s",$val);
$stmt->execute();
$result = $stmt->get_result();
while ($row = $result->fetch_assoc()) {
echo $row['name'];
}
$stmt->close();
When connecting database as a normal variable such as this works.
$stmt = $conn->prepare("SELECT * FROM countries WHERE id = ?");
However, I get "Call to a member function fetch_assoc() on bool" whenever I tried to call my connection as a function.
What am I doing wrong with this code?

Answer 1

After searching for a while and based on this answer, I was able fix my problem by declaring a variable for connection. However, this doesn't explain why directly calling connect doesn't work. Can somebody explain to me why the first way doesn't work?
$db = connect();
$stmt = $db->prepare("SELECT * FROM countries WHERE id = ?");