There is always a limit, even if it's not written down. But that doesn't mean it's zero. They are still writing down how much time off you take, even if they'

There is always a limit, even if it's not written down. But that doesn't mean it's zero. They are still writing down how much time off you take, even if they're not writing it down where you can see. But that doesn't mean anyone reads those numbers. Take some vacation. It'll prevent burnout, so it'll be good on net for your productivity. If they really do fire you for taking vacation, well, unemployment is kind of like unpaid vacation, so at least take some paid vacation first.