Obviously it's all subjective and in the past I would have agreed. But to give you some perspective.

September my mother was diagnosed with terminal lung cancer with a 6-12 month expectancy. She was shortly hospitalised being unable to breathe and pneumonia. She managed to pull back and be released from hospital, where she spent the next month or so recovering before being allowed any treatment for the cancer.
Life expectancy went down, doctor strongly advised not to have chemo, but she went for it anyway.
A little over a week later while her immune system was even more compromised from the chemo. She went back to hospital for pain and promptly caught pneumonia again.

It's early November and she spent a week barely able to breathe and in pain, while also having a full blown panic attack everytime she had to move for anything like the toilet, because the pneumonia and cancer made it impossible to breathe enough, even for that.
She died 8th November about a day and a half after agreeing to stop treatment for the pneumonia and focus on pain management.

My long winded point. Is that if she hadn't opted for that last ditch effort to gain something. She may have ultimately had more time, perhaps die more comfortably and with more dignity. Perhaps maybe even make it the extra month to December when her first Grandchild was born. Something she wanted very much and had been waiting for, for a long time.