Agile (or rather modern management) converts human capital into capital as fast as possible. Considering the endless supply of developers and lack of accountability there is no downsides to doing that, you are an externality.

Where can you get an endless supply of (good) developers from?

If you only hire young, there will be new yield every year.

There's a new yield of 40 year olds every year, too.

That doesn't make it endless.

Green cards

There's an endless supply of green cards?