Everyone who has played a strategy game will recognise this principle. Because very often this is the case. Some spend time and resources on good, high quality units, while others just massproduce cheap, low quality units.

Accidently the same principle can also be used in context with the second world war. Germany had tanks and better weapons than Russia, but Russia had a huge amount of soldiers. In many of the battles along the eastern front the Germans high quality weapons proved very efficient. But when the Germans first tried to innvade Russia through Norway, their tanks and weapons proved inefficient as the Russians where better clothed and therefor proved more efficient during the long hard winter.

What is better quality or quantity ?
Depends on the context I guess.