When Do You Design?

In the softor development life cycle, when do you design? Boy, that's that may be the most fundamental question in all of softwore design. You simply cannot design a computer system up front, a system of any size, and get it right. So i think design is a continuous thing that happens throughout a life. The lifecycle project never ends. You do some at the beginning, it's always going on. As substances become more mature, typically you spend less and less time redesigning. But recognize the fact that you may some day discover that even a very old system that you thought was perfect,. actually now no longer is serving the needs of the system.