If you're still using pen and paper or traditional CAD software to design your kitchen, you're fighting a losing battle. These tools are simply not ideal for kitchen design. Pencil drawings are slow, sloppy, and hard to modify. Whereas, CAD was designed with machining metals in mind, not wood.
Kitchen design is all about creativity and flexibility, and there are still so many different aspects to consider: the cabinets, the appliances, the countertops, the layout. Designing each blueprint sketch on its own is a challenge, never mind trying to accurately display how they will all come together in the end.
With pencil and paper, or CAD, all this planning, consideration, and visualizing can take time - time that you don’t have when you are on a deadline.