Write documentation first, then build
I don't know...
When I start something new it's often spontaneous. I have this idea I'd like to try and then I start hacking.
And while I hack at the keyboard and create the basis I think of the long term.Having to do double work, write a document first and then repeat the same in code is extremely counterproductive. Motivation plays a big role. Repetition is not fun. Most projects never get finished. There are always obstacles and some are really hard. But you won't know them from writing documentation alone.
And if you write documentation ahead of time it's very likely this documentation will not fit the final product, at 1st release time.Having a general outline with key features is ok. But fully-fledged documentation is over the top.That's my educated opinion at least. Motivation is very important for me, especially if I don't know for years if this thing I'm building will be used by people at all. Single developer.If there were dedicated people for tasks, that'd be different, probably.Also you can't take the established business and say they all had a memo or document and that's the reason why they succeeded. That's a really long shot, IMHO.