With thousands of job applications pouring in everyday, it's no wonder Google has hiring down to a science. True to form, the search giant has scoured its data over the years in hopes of determining what attributes successful employees share and which hiring strategies actually expose those attributes. In a new interview with The New York Times, Google's senior vice president of people operations, Laszlo Bock, shared what he's learned from this research about how to hire effectively.

Here are some highlights:

1. Brainteasers are useless.

For years, Google's most famous and feared hiring strategy was asking applicants questions that were seemingly impossible to answer, like, "How many golf balls can you fit into an airplane," and "How many gas stations are in Manhattan?" In theory, they were intended to measure potential hires' ability to think analytically. But in practice, Bock tells the Times, "They don't predict anything. They serve primarily to make the interviewer feel smart."

2. No one is good at hiring.

Several years ago, Bock explained, Google looked over tens of thousands of job interviews, reviewed the scores each candidate received, and assessed their subsequent performance. They wanted to determine if there was such a good thing as a good hirer. There wasn't. "We found zero relationship," he said. "It's a complete random mess." Now, Google uses a consistent rubric to assess candidates, Bock says, "rather than having each interviewer just make stuff up."

3. In leaders, the most important quality is consistency.

The toughest jobs to hire for, according to Bock, are leadership positions, because the characteristics they look for are "more amorphous and ambiguous" than the qualities they look for in, say, a programmer. But among these intangible qualities, Bock said, the most critical is consistency. "If a leader is consistent, people on their teams experience tremendous freedom, because then they know that within certain parameters, they can do whatever they want," he said. "If your manager is all over the place, you're never going to know what you can do, and you're going to experience it as very restrictive."

4. Employees score their managers.

In most companies, employee reviews are totally lopsided. Managers get to review their staff, but the reverse is rarely true. At Google, though, employees get two opportunities a year to fill out what Bock calls an "upward feedback survey" about their managers. The survey measures things like whether a manager treats the team with respect and outlines goals clearly. Google collects the data on each manager and shares it with the manager directly. "We've actually made it harder to be a bad manager. If you go back to somebody and say, 'Look, you're an eighth-percentile people manager at Google. This is what people say.' They might say, 'Well, you know, I'm actually better than that.' And then I'll say, 'That's how you feel. But these are the facts that people are reporting about how they experience you," Bock says.

5. GPAs and test scores don't matter.

In the past, Google was known for asking potential hires for a copy of their college transcripts and test scores. They've since given up on that strategy, because, Bock says, "After two or three years, your ability to perform at Google is completely unrelated to how you performed when you were in school, because the skills you required in college are very different. You're also fundamentally a different person. You learn and grow, you think about things differently."