When the Federation’s attempts at encouraging research failed dismally they took another route to gain new technology. While the Collective now had ships which were significantly more powerful than those of the Federation, they were far from invulnerable. Especially when overwhelmed by superior numbers. Collective ships were still being beaten and destroyed, though not before inflicting horrific losses on the Federation.
The Federation collected the scraps and remains of those Collective ships and bred a class of slave intelligent enough to unravel the workings of the Collective’s new technologies while still docile enough not to turn on their masters. Slowly, oh so slowly, the Federation’s technological level began to climb.
That wouldn't have been enough to turn tide of the war on
