How does one go about improving this in a big corporate company? Our development team is focussed on shipping, but most of our delays come from the business cha

How does one go about improving this in a big corporate company? Our development team is focussed on shipping, but most of our delays come from the business changing their mind and changing requirements constantly. The people who act as the bridge between development and business just side with the business. Anything that goes wrong is blamed on our development team. It’s probably just a hopeless situation and time to move on.