In my defense, I think that was a special case. This was a product to be certified as a medical device. Regulations require keeping records of all changes to the code that can be linked to well-defined "software requirements" and "stakeholder requirements". This can be done in a complex spreadsheet or by linking issues/merge requests in a certain way. I chose the issues. Also, as the product might affect health outcomes, I felt responsibility to make the product as solid and maintainable as possible.
Who decided to be compliant at this stage of the company, you or whoever is in charge of business operations?
> I felt responsibility to make the product as solid and maintainable as possible
Was this responsibility conveyed to you or did you make this decision on your own?
I'm clearly making an assumption here, but this reads like a case where both sides had a misunderstanding about how engineering time is spend. They trusted you with some autonomy to get things off the ground and found out you are making business decisions on your own that don't fit into resource constrained startup operations. There is always a trade-off and corners can be cut, and my advice is to be upfront about the general approach about those and find out how much they are willing to invest in robustness and product quality at a certain stage.
Medical regulations often pierce the corporate veil and create personal liability for the developer/whoever. He may not have had a choice. If you're asking your employees to commit crimes, expect high turnover.
> In my defense
Reading through your story and comments, this seems to be your main problem. Better communication might be helpful but you have to be more open to feedback and criticism. At the risk of sounding rude (not my goal) this post reads like a plea for validation. I don't know you and I hope I'm wrong, just going on what I see here.
Seems to me like OP had an absentee boss who ultimately threw them under the proverbial bus.
So I stopped tracking things meticulously in Jira and only kept basic notes of what I had done. Worked out fine.