My distressing tendency to see the other person's point of view to the exclusion of my own. I visited a cobbler at lunchtime to ask if the blister-inducing blemish in one of my new boots was fixable. He said yes but he'd have to keep the boots for a while and charge £20, and then asked me why on earth I hadn't taken them back for a replacement instead. I couldn't think of any good reason, so I left the cobbler's feeling very stupid. Ten minutes later, I remembered: I'd wanted to know whether the problem was cheap and quick to fix, because if so then I'd prefer to have it fixed and not have to break in the replacement boots all over again! After he told me it would take days and half the price of the boots, then it seemed obviously sensible to try taking them back first. But while I was talking to him, all I could see was the obvious stupidity of my course of action from his point of view, and I'd totally forgotten why I made sense really.

People who can't distinguish between a premeditated punishment and an inescapable logical consequence of their action, and who expect mitigating circumstances to protect them from the latter as well as the former. ‘Sorry I didn't do X for you; I had no idea you needed it, but I would have if I'd known.’ ‘Well, that wasn't my fault; I couldn't tell you, because my phone (as it might be) was on the blink.’ I don't doubt it was; but that doesn't change the fact that if I don't know something needs doing, I'm unlikely to spontaneously do it! It's not as if I deliberately didn't do it to punish them for their failure to tell me about it. Just because you weren't to blame doesn't mean I was.

The spurious ‘of’ in phrases of the form ‘it's not even that funny of a joke’. Only remarkable, really, because it's not one of my usual pet grammar peeves; but I've encountered it several times very recently, so it's temporarily appeared in my top ten. I don't care whether you can tenuously justify the presence of the ‘of’; the additional word costs time, effort and space and the phrase is definitely correct without it, so why not save everyone the hassle and leave it in the inkwell where it belongs?

The way hot drinks accelerate their cooling when there are only two mouthfuls left. It honestly shouldn't be too much to ask that I should be able to drink my coffee at a constant slowish rate and have it still warm by the end of the cup; but no, the laws of physics have to get all ‘heat capacity’ and ‘surface area to volume ratio’ about it. If there is a Creator, he obviously doesn't drink coffee, or he'd have sorted this one out at the start of the universe.