What it means
A wake-up call is that moment something finally smacks the fog out of your head and makes you deal with what's been going wrong. It started as the literal hotel phone call to wake you up, but now people use it for any harsh reality check that jolts you into sorting yourself out.
Usage examples
"Missing my kid's school play because I stayed late at work was a wake-up call, so I'm setting boundaries and leaving on time."
"Skipping the parents evening for a deadline was a proper wake-up call, the kid teacher emailed three times and now I am putting school stuff in the work calendar like meetings."
"Discovering the diabetes risk at the annual check-up was a wake-up call for dad, he cancelled the chippy subscription, joined the walking group at the leisure centre, lost two stone by Easter."
"Getting my card declined three times in one weekend was a proper wake-up call, so yeah, I finally opened the banking app and faced the carnage."
"When the coach benched him for turning up late again, that was the wake-up call he needed and suddenly he's setting five alarms like his life depends on it."
Where it comes from
It comes from the literal wake-up call hotels used to give guests by phone so they wouldn't sleep in and miss their plans. From around the mid 20th century, English stretched it into a figurative phrase for any sharp shock or reality check that forces someone to pay attention and act.
