Even that isn't the mistake at all. It's a good strategy to prepare to do a lot, then when some things go wrong, at least some of all things we're prepared for work. If you set the goals too low, you'll do much less. Therefore, the basic plan was to do the most of the work during a short time period. But they prepared to be able to do something interesting for much longer, if everything goes as perfect as it ideally could.

The mistake would be allowing others to feed on smaller-effect non working stuff instead of the things that amazingly worked.