I think I've decided that one thing that annoys me the most is when someone uses an emotional appeal to influence a medical decision. For example, I was talking about how I don't think any vaccines should be compulsory. None of them are compulsory in the UK, though of course they're strongly recommended and most parents opt for their children to receive them. To me, this shows that they don't need to be mandatory in order for there to still be a large uptake for them. I simply object to any medical treatment being compulsory, for we should have the right to informed consent. I've stated before that I'm not anti-vaccine, but neither do I think all vaccines are necessary for all children.
Anyway, there have been a few times when I've mentioned my views only to be met with an emotional appeal. This usually takes the form of "but what if your child isn't vaccinated for x and comes into contact with someone who is susceptible?!" That could be a pregnant woman or ill child or whatever, but the emotional appeal remains the same, really.
While such an appeal is quite powerful, it is not a good basis for a decision, in my opinion. Medical decisions should be based on looking at the actual risks and benefits for action or inaction, not on an emotional appeal about what might happen. Yes, it's good to take others into account if the decision might affect them, but again the risks need to be weighed.
I think the reason it annoys me, besides the fact that it's not a good way to get informed consent, is because this reaction is given without realising that my children have had adverse reactions to some vaccines. Like, the kind of reaction that it says on the package insert indicates that that vaccine shouldn't be given again. There's no permanent damage as far as I can tell, but it does play a part in my vaccine decisions. Again, it comes down to weighing all the risks and benefits, and this is best done in a logical manner and not with emotional appeals, in my opinion.