The book "Startupland" that chronicles Zendesk talked about this exact problem. One of the 3 founders had "family" to take care of and because of that, he wanted a higher salary. The 2 other founders were thinking, "what?!?
you're not the only one making sacrifices here!"
After some discussion, the 2 other eventually agreed to it but they really resented it and it was a source of bad tension for a long time.
Zendesk eventually got to the IPO so the 3 got past that unequal salary episode but the soap opera drama doesn't seem to be something you want for a struggling company.
(Side note: I think it's unfair to downvote jacquesm for bringing this up. Even if you disagree with his opinion, it's still worth leaving the text ungreyed to discuss pros & cons.)
 coincidentally, Zendesk is one of the companies in Point Nine's portfolio:
(However, author Christoph Janz joined Point Nine in 2011 and Zendesk started 2007 so he may be unaware of their early salary drama.)
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