It's interesting how people are calibrated differently it comes to measuring 'hard work'. The difficult thing about startups is that the correlation between hard work and success isn't very strong.

It might be the case that a PhD is very hard. My idea of it is just based on third-party observation and discussions with people who have done it. I suppose some people have a harder time than others.

I worked on two open source projects for 6 years in total for about 20 to 30 hours every week in addition to my 40 hour per week day job. My first project had around 500 commits and was about 10K lines of code. My latest project has well over 1000 commits and probably 15K lines of code (I contributed about 80% to 90% of the code and it went through several rewrites). I also wrote the documentation for the project mostly on my own - There are almost 30 pages of technical documentation - About 15K wordcount. I did it for $0 - All I got out of it was experience, industry connections and some nice job offers.

I feel like I worked hard. Almost certainly harder than anyone I know. But I know for sure that some people on HN will read the paragraph above and think that I'm actually a lazy entitled millennial.