We can use such approach if we are sure that `"constructor"` property has the correct value.

For instance, if we don't touch the default `"prototype"`, then this code works for sure:

```js run
function User(name) {
  this.name = name;
}

let user = new User('John');
let user2 = new user.constructor('Pete');

alert( user2.name ); // Pete (worked!)
```

It worked, because `User.prototype.constructor == User`.

..But if someone, so to say, overwrites `User.prototype` and forgets to recreate `"constructor"`, then it would fail.

For instance:

```js run
function User(name) {
  this.name = name;
}
*!*
User.prototype = {}; // (*)
*/!*

let user = new User('John');
let user2 = new user.constructor('Pete');

alert( user2.name ); // undefined
```

Why `user2.name` is `undefined`?

Here's how `new user.constructor('Pete')` works:

1. First, it looks for `constructor` in `user`. Nothing.
2. Then it follows the prototype chain. The prototype of `user` is `User.prototype`, and it also has nothing.
3. The value of `User.prototype` is a plain object `{}`, it's prototype is `Object.prototype`. And there is `Object.prototype.constructor == Object`. So it is used.

At the end, we have `let user2 = new Object('Pete')`. The built-in `Object` constructor ignores arguments, it always creates an empty object -- that's what we have in `user2` after all.