Decision time: budget optimization is not just a sub-category of season choice, it is the overall framework. You do not choose a season and then see if the budget fits; rather, you set your budget first and then adjust the season, companions, or transportation accordingly. A family with a rent to pay and children in school in Brussels cannot simply choose the low season without considering financial and family constraints. It is a matter of clear priorities and financial planning first. Set the budget, then everything else.