Lies, Damn Lies and Statistics

A phrase in all probability coined by Disraeli about probability (and other things.)

The probability of a random event happening in a certain hour is 4% (1 in 24) and the probability of that event happening in the 'day' time is double that of it happening in the 'night' time. ie 16 to 8 (or 2 to 1)

So why does Jaki's mobile phone's super loud low battery warning beep always, always, always go off in the middle of the frigging night?

(that's a rhetorical question btw, I don't want a flood of comments about skewed distribution and standard deviation, thanks very much.)