Consider that a successful product will be maintained for years. It is highly likely that a people will come and go. Documenting already running code will inhe

Consider that a successful product will be maintained for years. It is highly likely that a people will come and go. Documenting already running code will inherently have less priority (both in the eyes of upper management an developers- the temptation to jump on the next project is huge). So if you don't start documenting first- odds are you never will.