Hmmm. I get your issue now. Could still be the issue I said (incorrect order in the route list).
But it could be different,
So to give it context:
A=Industry, B=City, C=Raw Materials.
Route order is A-B-C.
Raw materials walk from C to B; then get picked up by train at B and not dropped off at C, but at A.
The line between B and C is therefor obsolete, the trains waste profit by driving this part.
If I were to make a guess, I’d say the time it takes to wait at station C before being picked up is longer than the time it takes to walk to station B. Because the round trip is equally long from each station, it needs a way to pick one if you (in this case: the Devs) don’t want to use a “just pick one” with a random-generator. Since making routing choices logical is one of the points this game wanted to bring, they have picked one of the following two methods:
Line order (When chosing between two (or more) stations where the total travel time is the same, pick the station that is serviced before the other(s)).
This is why I asked to switch the order around, if it makes no difference in delivery time, they might go to the first station in the route list after the final destination(A), which in your list would be B. Because B will always be serviced before C on the line’s direction.
Closer to final destination(In which case it will also always go to B)
This would be a cheap method, because it doesn’t take into account the route length, whether the route is direct or indirect. They most likely havn’t picked this method. But your example makes it testable.
If switching the line order doesn’t change anything, I can’t imagine the following option not working.
I think if you seperate the two (into C-A and A-B), the problem will likely go away.
Because this creates a seperate frequency time for the C-A and B-(through C)-A options, rather than the travel time and frequency time both being exactly the same.