The Irish are generally known as a fairly relaxed bunch. "Grand" is one of our most used words, and there's very few things that don't turn out to be grand.
Every time something classically Irish happens (such as shops closing for the day 'cos of good weather!), we laugh and say "yup, only in Ireland!"
Basically, we're a nation who make up our own rules depending on how we feel.
Case in point? This hilarious express checkout sign spotted on Reddit in Scally's shop in Clonakilty, Cork.
10 items? Grand. 12 items? Ehhh... That's grand too.
What if we have 11? 13?!