If you are starting a festival and there is a colonist who's zone restrictions do not enable him to participate (cannot grab 4 wood) then the error message for the festival is inaccurate and unhelpful.
For a lantern festival it will claim that you lack wood, by exactly 4 units, (so if you have 10 colonists who need 4 each, it will say you only have 36, even if you have thousands of units, and if you remove a colonist from the list, it will update it to say you have 32, until you remove the colonist who specifically cannot access wood)
If this error message simply was replace with "some colonists cannot access wood" it would give better troubleshooting tips. Or, if restrictions simply did not apply for festivals.
Thanks for the suggestion, I can see how this wording would be confusing. I'll make a note of it in my internal docs. Sorry for the frustration there!