I would go further and say that one of the basic principles of business is that they should be forward looking. 

Done well the budget and forecasts are a great way to get the staff, managers, owners and funders all on board with common objectives and expectations.  It is inevitable that the conversations that cause that alignment are likely to be time consuming, uncomfortable, and possibly confronting.  

Done well the discipline will make for an agile business with problems quickly understood and solutions adopted with a minimum of fuss or re-litigation.  In addition, managers will have a clear understanding of how the business makes money allowing them to make effective commercial decisions with apparent ease.

I really enjoy working with clients on their budgets because it invariably creates opportunities to improve their profit.