Interestingly, the only piece of technology that Earth had and they didn't, was weapons. It was the only technology and invention that had not been conceived of on Planet Zero. Years and years later, when they saw that the humans had invented guns and bullets and bombs, they were very apprehensive.
When the findings were reported back to the leaders and their king, they all unanimously voted against the construction and use of weapons on their soil. They would never countenance violence on their land, and they were filled with misgivings at the thought of their comrades living out their lives amidst such violence.
If they had wanted, they could have perfected brilliant and terrifying weaponry capable of wiping out entire planets within minutes and turning it into ash. However, since they always based their decisions on logic and reasoning, they were yet to meet conflict with head-on violence. And there never arose a need to make arms. This decision continued to be validated as violence kept rising on earth, with no sign of stopping.
After a lengthy conference, it was reluctantly decided that they would not meddle with the progress on earth, no matter how heinous it seemed to be. Years later, some of them regretted their non-interference thinking it might have been better had they put an end to that beastly invention. However, the elders and the most learned of them said, "It would have been a temporary measure. From what we know of humans, they are filled with entirely too much passion and rage that fuels into violence. It would have erupted again and again, with or without our help." And so it was with sombre moods they watched humans on earth destroy each other and the planet over time.
For all their technological advances and breakthroughs, evolution at Planet Zero had been lopsided.
Where they excelled in all scientific and mathematical fields, their hearts and souls were devoid of any emotional fulfilment. They didn't feel anything in extremes, not even ambition. Duty and work were paramount for them, and a preference for orderly living. Everything had a time and place, every action was governed by a set of protocols, and there was no frivolity of any kind, ever. There was no fun and games or laughter, even during their childhoods.
This is not to say that they were devoid of all emotions. They were just very, very diminished so as to be almost negligible. They did form attachments and friendships but were sorely lacking in passion and love. There was no song to be heard anywhere, nor dance or plays or any kind of cultural activities. Zerowans didn't seem to need it.