SMS text delivery has always been sporadically unreliable for me. The cases where the messages are delayed by several minutes or hours are almost as problematic as the cases where they never arrive at all.

It doesn't seem to be specific to any country, though some are worse than others. Definitely seems to be a "best effort" service everywhere.

It's unneeded because phones have affordable/free access to the Internet these days, SMS is a relic of the 20th century.

I have a US number and live in Switzerland. At least for me, I only receive SMS messages whenever I visit the US -- the rest of the time they're just dropped and I'll never see them.

(Doesn't really bother me, my friends and I all use WhatsApp/etc. anyway.)

n=1 though, maybe this is some quirk of my phone provider.

Somehow they're unreliable just in the US. I had someone think I was mad at them because when I texted them to hang out it never made it. Had to remember to switch messaging apps.

I think they were on a cheap prepaid plan though.