Vegeta Effect

When the desire to surpass your rival (friend or enemy) motivates you to accomplish the seemingly impossible task/goal you are competing to achieve.

In reference to Dragon Ball charactars;

The painstaking task/goal is generally achieved first by the rival (Goku), which causes you (Vegeta) to accomplish the task/goal out of desire to surpass your rival.

Goku and Vegeta Backstory--
Goku was the first to achieve Super Saiyin (SSJ), leaving Vegeta extremely jealous of his next level power. It was an incredibly difficult task to go SSJ but the burning desire inside Vegeta to surpass Goku allowed him become SSJ without suffering the same strife that Goku had to endure (the death of a close friend named Krillin).

*John and Smith are competing in a video game, John is the first to beat a series of difficult missions after several attempts each*

Smith: I couldnt beat it untill you did, then it was easy.

John: That's the Vegeta effect.