That's just completely obvious. If you're not having fun at a startup, you'll be miserable and you won't be doing your startup any favors.

I'm at my fifth startup now. All four previous ones have been both fun and profitable. My rule of thumb for joining and staying at a startup has been: have fun, believe that the company will produce something of value, be reasonably compensated. I have decided not to join (and have also resigned) when any of these failed to apply.

I've made it a point to enjoy my life. I like my living arrangements, my meals, my free time, and especially my work. I like the company I work for, and the people I work with.

I have refused jobs solely on the basis that I didn't like what the company stood for, even though I knew I could get a substantial pay raise by going there.

Anyone who can't say "I'm having fun" right now (barring the rare emergency) is doing life wrong.

Hackers do everything they do for fun. If it's not fun, it's not worth doing. It's important to note that fun things can be hard and very challenging, be it a grueling mountain bike ride or taking an idea all the way to a multi-billion dollar acquisition. Talking about how difficult something was is good for show, but hackers are often a lot more likely to dwell on how fun their journey was and all the awesome things they saw and learned.