Enough resources at Armageddon is a message you will see if you go into negative crop production, and you want to build something for which you lack the resources. For example, when your population and troops are using 500 crop per hour and you are making only 450 crop, you will have -50 crop. If you then want to build something for 1000 wood, clay and lumber and 500 crop, but have only 600 of each resource and produce 100 wood, clay and lumber an hour, you will not have enough crop for the upgrade when you have enough of the other resources. You will have only 350 crop once you have enough of the other resources, which is not enough to build the building. The message appears in the space that would normally tell you the time at which you can build or upgrade a new resource field or building.
See also Crop usage.