Sorry, I just thought it was kind of an odd thing to say. Usually you don't know that a tire is going to be a PITA to mount until you discover it the hard way, which means after you purchased it.

In my case, it was 28mm Vitoria Corsa G+ tires and H+ and Sons rims. Neither of these, alone, should be a cause for concern, but I cannot mount that tire on that rim with anything short of a tire jack. I won't be buying them again, but I'd still like to get my $80 worth out of those tires.

I don't have much experience with tubeless, but I do get the sense that most tubeless tires can be a real struggle.