This question already has an answer here:
- Can you choose to fail a saving throw? 7 answers
I was reading through the Monk rules in D&D 5e when I came across this section in the rules for Quivering Palm:
When you use this action, the creature must make a Constitution saving throw. If it fails, it is reduced to 0 hit points. If it succeeds, it takes 10d10 necrotic damage. PHB pp.80
The standard expectation of how saving throws work is that if someone's attacking you, failing your saving throw brings worse results than succeeding, so you naturally want to succeed, and your attacker benefits if you fail.
However, that isn't always the case. Quivering Palm is an example which violates that standard expectation. Suppose you're on very low HP, or you're a very low-constitution wizard with less than 100 max HP to begin with, or you may want to avoid having to make death saving throws, or worse yet, a combination of these things! At that point, failing the save and dropping to 0 HP may be a far more appealing than succeeding, taking 10d10 necrotic damage, and risking dying outright.
How do you handle this situation that seems counter-intuitive to the rules? Can the rules be reinterpreted so that the best option you're left with is not simply to fail your saving throw? Something that, like normal, gives an advantage to success over failure? Especially since, as daze413 mentioned in comments to an answer here, the character doesn't know he should fail.