Leaving a startup is a personal decision that can be very rational; I don't criticize your decision to leave. I am critical of your understating your importance to the business. I think that 1/3 of the company would have been far too much, but 0% seems far too low.
That's not what everyone is going for.
Take cto. When it's founders and maybe an employee, cto is a full-time dev.
Then you get funded, and four months later the engineering team is 4-6 people. The cto is now a line-level manager who codes a bit. It's a completely different job.
Then you get the next round, and suddenly the cto supervises 2-4 line level eng managers and has to decide if (s)he wants to be cto or dir-eng, because those roles are about or have already split. This, also, is a completely different job.
At each step, it's a completely different job.
Your company needs to be prepared for founders who don't want, can't, or aren't good enough at the next step that is required of them. Because the job literally completely changes every 2 years. Or sooner.
The product went live and was even used by some people. Eventually I ended up in a place where it was clear to me I disagreed with the direction of the business and the CEO leading it. I for one am glad there was a cliff.
Because I left and when I did my co-founders continued to work on that business. As far as I know they’re still at it.
That was over six years ago. The code I wrote is likely of VERY little value in the grand scheme of things.
The value I added in thoughts, ideas, advice etc. is probably about as valuable as people my co-founders have had several dinners with over the years at this point. If I had walked away with 1/3 of the equity that would have put the other two co-founders in a horrible situation and would have been completely unfair of me to do.
The cliff did its job. You vest to protect all parties and because it’s just the right thing to do. Take it from someone who walked off the “cliff”.
I’ve started multiple companies since then. Each has had a vesting schedule and a cliff for all founders.