That depends on how one defines success. Was Einstein successful? His work was pure research, and he was never financially successful, but his work resulted in a greater understanding of nature, a result we all share. Someone could argue that, because Einstein was never wealthy, therefore his work failed, but the defects in that argument are clear.

From a political perspective, pure research funding is certainly a lottery, but that doesn't address the question of what kind of science produces most of our insights into nature. The answer is pure research.