Ask HN: What is a 'real vacation'?

Sam published on The Macro yesterday on how to run a late stage startup (~2 years in). Great advice for anyone interested: http://themacro.com/articles/2016/07/later-stage-advice-for-startups/

At some point in the post he mentions:

> "And remember to take vacation yourself. We often see founders that go three or four years without ever taking a real vacation. That may work for a year or two, but you will burn out."

What does that mean? I go camping every year for 2-3 days, doesn't change me at all..and I chill with my non-startup friends every week anyways not like I'm on that 24/7 grind 80-hours week hustle that everyone brags to be on. Am I missing something out that I'm not going to Honolulu for 2 weeks?