[BobTheCoder]

Indeed I agree competition is necessary.

With the right system though competition between individuals is sufficient. Humans will try and get ahead to woo their spouse by whatever means are available. Having individuals compete for prestige and salary is enough to engage humans to strive for excellence.

Group competition doesn't relate to this aspect though. In a one group system individuals incentivized by individual reward won't be lazy or they lose out so group competition is not necessary.

For example, take a series of tribes in one area competing for resources. If all but one tribe die out due to disease, the individuals of that tribe won't suddenly become lazy. Why? Because they still need their personal acclaim to attract a mate and be successful.

In a multi group system (capitalism) there is no incentive for groups to compete (as in increase consumer value at the expense of profit) without competition, so yes in this system group competition is necessary. However, this attribute is not true of all systems.