A company with the means to do so will grow, as much out of principle or reflex as necessity. Middle managers hire as many as they can justify. The people at the top watching the bottom line are many levels removed from the $200/hr contractor doing trivial or unimportant work so they don't know to fix it. The middle manager/director has more to gain by increasing their head count than by being efficient.
And while hiring is easy, firing and laying off is hard. So the path of least resistance of an org is to grow larger than it needs to be, as long as there's profit or investment to feed it.
And while hiring is easy, firing and laying off is hard. So the path of least resistance of an org is to grow larger than it needs to be, as long as there's profit or investment to feed it.