My mates just broken up with his partner of 8 years (together for 5, married for 3) because they literally never had a discussion about kids, he just assumed that was where they'd eventually take things and she just assumed since he never mention it he also didn't want any.

It's baffling to me that people can make it 8 years into a relationship and not have a plan, i always know the intentions of my partners before commiting and that determines the seriousness. Outside of them doing a complete 180 on their views i think it's a decent system.

I have had someone do a 180 after 3 years though, but that was on moving abroad and to be fair even after we broke up i didn't go so she was definitely right lol.