Not knowing your budget can limit your team members. For example, when you hire people for a project they work at a specific rate. So if you do not know your budget it can be problematic in getting the team members you want. So if you know the budget, you can timeline your project much better and hire the team members according to your budget. In addition, if the project manager knows the budget, he can manage your progress of the project and compare how much money has been spent vs what the budget is. This will allow the project manager to avoid any of the issues such as stopping a project, putting more responsibility on team members, and avoid any confusion or “set” budget issues in the middle of a project.