On the real railroads such as Amtrak, Their route may take them down along the Mississippi River but the tracks on that side of the river might be flooded. So they then will take the tracks across the river up where they met it and cross there on to a competitor tackage down the other side where it is not flooded. Like with Amtrak they have to pick up a crew that knows their tracks until they are back on their own route again. But in the case of arriving at the normal crossing of the river the only way to head east was to turn west and cross the river where there was a wye on the other side.(there was no track to turn left and head on your regular route. They would pull the whole train through the wye and back up through the other section of it then return back across the river on it’s regular route. On another case the UP Coal train comes across the Wabash River. Where he is going there is no right turn after crossing. So he will travel through town to the wye that connects to the competitor’s route, travel through that sharp wye change crews (he is on different railroad now) and then follow it as it circles town and reconnects south of town. There are many ways you can use the wye. track and turn a round.
Newman

The Wyes are used in real operations . Among them would be a train that would be doing a milk run delivering and picking up along a section. But they need to get back to the yard and running the train backwards works but is difficult at you need eyes from the rear of the train. So they would work deliveries to and return to points that would have a wye to turn the train or at least the engine so they can ride facing forward. Here at home there is a Wye that is near the yard and it normally connects to another railroad. Up the tracks there will be another wye maybe at another rail crossing or another switch yard. Another way to not have to use a wye track would be to have a pair of engines facing the opposite directions and they would pull into a siding,uncouple and go back to the other end of the train on the main track and reconnect to the rear of the train. Your other engine is now the lead engine.
Newman