Ronald Wayne was an original partner in Apple with Steve Jobs and Steve Wozniak, but decided the business wasn't for him. He left. To make things official, Markkula bought out his stake in the company for $1,700 in 1977.
In 2012, Wayne wrote an essay on why he left Apple. It's quite good:
"I didn’t separate myself from Apple because of any lack of enthusiasm for the concept of computer products. Aside from any immediate apprehension in regard to financial risks, I left because I didn’t feel that this new enterprise would be the working environment that I saw for myself, essentially for the rest of my days. I had every belief [it] would be successful but I didn’t know when, what I’d have to give up or sacrifice to get there, or how long it would take to achieve that success.
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To counter much that has been written in the press about me as of late, I didn't lose out on billions of dollars. That's a long stretch between 1976 and 2012. Apple went through a lot of hard times and many thought Apple would simply go out of business at various times in its maturity. I perhaps lost tens of millions of dollars. And quite honestly, between just you and me, it was character building."