I think there's some ebb and flow in what practice is ideal. There are benefits to a detailed up front design. Conversely there are benefits to jumping straigh

I think there's some ebb and flow in what practice is ideal. There are benefits to a detailed up front design. Conversely there are benefits to jumping straight into code, to get feedback and let the design emerge through real experience. Unit tests are a nice way to define interfaces. Conversely sometimes it's better to discover an the ideal interface organically rather than setting it in stone up front. Some of it is just differences in what medium you perform design. People want the medium to be like playdoh so it can be changed. Before they cast it in marble. Some languages are more like marble, some like play doh. But don't ever delude yourself, thinking you have found the best way to design. Source control is not really software development. It's a very good thing, but in the same way that eating a healthy lunch will assist creating things.