Right now, in the warm state of being able to think calmly about the situation, you'd have absolutely no reason to think they'd stop hitting you with the wrench

Right now, in the warm state of being able to think calmly about the situation, you'd have absolutely no reason to think they'd stop hitting you with the wrench once you've given in to their demands. However, in the time itself, your brain would go into it's 'survival mode' and logically tell itself that if you give in to their demands, they'll possibly let you live. Being able to override that preset state of mind is very hard to do, and why hostage-type situations work; whether you or a loved one is the hostage in question.