Creating documentation takes as long as it does to create the product.

I failed to consider the time it takes to document a project within the plan. Although I have ploughed many hours into this area, it is still not enough. Documentation is crucial to allow for clear communication across your team. Without it Carl will face bottlenecks or be forced to make decisions on the fly so he can continue with work.

I basically wrote the code and the specs and documentation for how the client and server talked to each other. — Tim Berners-Lee