Don't have the runway for that? Are you managing the startup as well as you could? Why did you tell your investors that you could do it in five months of dev time?
Source: I'm a trained sailor.
Engineers below the upper senior levels typically operate with an "infinite" mindset in making these choices. We all laugh at the relevant XKCD[0] because there's a grain of truth in there. This isn't a knock on engineering, it's just the nature of operating at the lowest levels. You become involved in the problem and you solve for local maxima.
Leadership done well is going to offering transparency to the people on the ground level, communicating timelines and strategy in a way that is relevant to the problem at hand, so people know, for example, how long they can spend solving a particular problem.
Where this sometimes goes wrong is, the higher you go in leadership, the lesser certainty there is. There are no "right" answers, there isn't perfect information, and yet, decisions must be made. If engineering is operating on different base assumptions, those decisions will look wrong (and they might be). And yet, someone needs to get people aligned and moving forward, because moving fast in the wrong direction is typically better than moving too slow, even in the right direction.
So, short-term, you have happy leaders who see releases as they want, and unhappy devs who are in a shitshow of code.
Long-term, if your startup is either acquired or starts to grow a strong revenue stream, leaders need to appease their new owners or their influx of new customers, and you can’t slow down because either a.) the new board needs to be impressed to justify their large acqui-investment, or b.) your new customer base is too big to risk losing. So you keep building on bad code, maybe squeezing in a few skunkwork refactored that only the dev peer reviewing and QA know about, and accept any delay on release as the result.
The approach should be somewhere in between, ideally with the engineering team being empowered to tell leadership “yo, we have a bomb of bugs just waiting to burst if we add one more feature with duct tape, let’s prioritize time to address it”.
If leadership doesn’t trust your team, then you have bad leadership.