"Unlimited PTO" vs work-life balance... how does that work?

Looking at jobs, and I see some (right now one at Harris Poll) that offer "unlimited PTO." I've seen this in the news once or twice, but I've never experienced it. Looking at Harris Poll reviews on glassdoor I see a mix of comments, including "unlimited vacation is nice" and "long hours, nights, weekends..."

So how does that work? "Unlimited PTO" sounds too good to be true so I assume it is too good to be true. What happens in …

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