The destructive capacity of technology was limitless.
As humanity continued to develop its technology to greater heights, people always managed to come up with better and more creative ways to kill a lot of life at once.
From developing antimatter weapons that were powerful enough to crack entire planets to spreading fast-acting viruses that killed a specific species of aliens faster than they could develop a cure, it was disgustingly easy for scientists and engineers to cobble together superweapons in their own labs and workshops!
Though humanity had also invested a lot of resources and attention into developing effective countermeasures, their R&D in this area had never managed to keep up with the pace of superweapons development.
This was a reflection of the universal adage that it was a lot easier to destroy than to create.