Despite what they have told you, that's never a real issue. If the project is divided into small tasks, if progress is not being made on these tasks, the management always has the right to steer the direction of the project or to reassign the staff tasked to it. This is how management can continue to control the expenses. As for estimates, even an AI can give those, probably better than what a human can, and without any stress.
So if you would hire someone to redo your bathroom or kitchen, you would hire them without an estimate and quote as long as they divide the project into small tasks?