Or look at it from the other direction. Company Z could borrow $1B for a new business project. What would it spend that $1B on? Overwhelmingly (50% - 70%) on employees, labor. So if Z can't borrow that $1B, the main effect will be reduced jobs and pay, and as G$ says, that flows backwards, so the 30% - 50% that isn't spent on workers, some is spent on parts, and the cost of those parts if 50% - 70% workers, so of the $1B that isn't spent, probably $700m works its way into the economy as reductions in wages.
If the economy worked differently and didn't require so many workers, then there would be more room to control inflation in other ways. But it doesn't.
Here, you can read to your heart's content on the Phillips Curve.
Historically, an inverse relationship seems to have existed between unemployment and inflation. Does it still exist? And why does this matter?
www.stlouisfed.org