They didn't explain why they were in a hurry to get even stronger, and the others also didn't ask about it anymore.
Well, it's good that Nathan and the others were aware that they couldn't just state the reason why they were stimulated to become even stronger, because it would just cause Ferman and the others, who had regained some hope, to panic again and their motivation to live would just fall to their lowest point.
They're already happy and think that they could live better after going to the south base as it's more secure, so there's no need to say that they had encountered even more dangerous zombies that would certainly cause more trouble for everyone in the future.
The south base was obviously one of the largest bases in the country, so the ordinary people living in their base could certainly be better compared to those that were already living outside, especially in the future when a lot of those zombies appear.
