There are thousands of stories where death, rape, theft, looting, etc have used by folks in positions of power to get what they want in these situations.
The obvious answer is to have competent government actors who can act quickly and protect human life without a financial incentive and disengage as situations improve.
You can demand all that and more if in the US healthcare market if the medical GoFundMe category is any indication. But that is perhaps too much of a digression...
Placing an upper limit means that you are less likely to be rescued at all, if the potential rescuer happens to not be a nice person (or is very risk-averse and rescuing you involves some risk).
In other words - if the person is nice, you do not need to have any limits, as they would not abuse the situation anyway. If they are not nice, with the limits they will not rescue you, but without, there is a chance that they will be overcome by greed and so will rescue you.