The other day, my wife went into a restaurant and ordered a cup of doujiang ('beancurd juice') to take away. When the lady handed it to her, she said, 'Careful, it's hard.' My wife had to ask her to repeat it three times before she realised it was 'hot', not 'hard'.
There was nothing wrong with the pronunciation: the lady was probably from the Philippines, where 'hot' would be pronounced as [hɑːd], using an American accent; but, being more familiar with British pronunciation, my wife heard [hɑːd] as 'hard'.
Given the context, this kind of misunderstanding should not happen. When someone hands you a cup of liquid to take away, there are not many things she could say apart from 'it's hot'. But, surprisingly, we do sometimes make mistakes like that.
