This test was supposedly given to people who wanted to study with the Russian chess school. They would time how long it took them to solve the problem, and based on that, determine how high they were likely to be able to achieve. If people didn't have the right way of thinking to be able to solve the problem quickly, they'd never be able to solve chess puzzles under a time limit in tournaments. If they had the potential, then the school would take them. And it was up to them to put in all the study, memorization, and training to fulfill that potential. The title refers to that use of the puzzle -- if you can solve the puzzle in the time limit, you have the potential to be a chess grandmaster.