Do you think relationships just run their course?

If what held them together was weak, they’ll run their course until it dissolves. Everyone knows how to keep a relationship strong. It’s been said a million times and it’s everywhere. Most just lack the commitment to the effort.

In a way I don't get that.
Anything that is so short lived, is a bit indicative of lust or infatuation or lack of commitment or something. If there is deep love/passion involved how could it...?

Many relationships last a life time. Plus we have relationships with spouses, family, friends, etc.. that last many a year, sooo.

I realize there are situations/circumstances that could cause it too though.

It takes both partners steering in the same direction.

You join people at different times on their own journeys through life.
Sometimes you're ahead of where they are, sometimes you're behind.
Only those who constantly feel they move together seem to last the course

If you're emotionless, yes

If it's a superficial one then yes.

I think every relationship has a period when things are less exciting...its just a matter of making things feel fresh

Yes, not many relationships last forever, but that doesn't mean they are meaningless. They can very meaningful while they last.

Of course I'm unqualified to answer such a question

for the most part yes. But some stay the course.

This is doubly true for robots.

yes they do. some longer than others

Some do, some don't.

Sad ...but true

No