Verb
go back to the drawing board (third-person singular simple present goes back to the drawing board, present participle going back to the drawing board, simple past went back to the drawing board, past participle gone back to the drawing board)
(idiomatic) To start again; to scrap a previous idea or plan and try again from the beginning.
After the original plan failed miserably, they decided to go back to the drawing board and come up with something new.
Our current use of time is not rational. There is therefore no point in seeking marginal improvements in how we spend our time. We need to go back to the drawing board and overturn all our assumptions about time. Richard Koch