If you're a groomsman at a wedding, you're not supposed to turn up four hours late, are you?
As a mate, you're not supposed to keep your friends up all night, fretting, freaking out, chomping at fingernails, wondering if you're going to survive the night, are you?
I'm asking, because Devon Conway's doing my head in.
But maybe that's just the fact I've barely slept these past few days.
You see the above statements lack any real context, so maybe this will help you get your head around why Conway is more than just a special cricketer.
When Devon and his fiancee Kim arrived in New Zealand in September 2017, my partner Courtney and I had also just arrived back in New Zealand, after I'd spent a stint playing cricket in the United Kingdom.
Devon's first training session with Victoria University of Wellington cricket club was also my first training session with the club, and as the new boys we struck up an almost instant friendship.
Whenever we talk, he genuinely cares about how I'm doing.
He always asks about my partner, about my dog. Heck, when he and Kim come around for dinner, he probably spends more time with our animals than us.
He has a huge amount of empathy, and I think that shines through, even at Lord's.
Some athletes have this public persona - Kiwis love a humble athlete who works hard and leaves it all on the pitch - but in private they're completely different.
I was once a sports reporter, so I know far too many of them to count.
Conway is as he seems. He's genuine. He's the real deal. And he's one helluva mate.