Originally Posted by EWR764

Despite the narrative ("UA can't compete at LAX", that was my initial thought too), I have it on good authority it had as much to do with performance as anything else, and perhaps more so. UA just doesn't have the right airplane for LAX-SIN... the 789 took a significant payload hit to operate the route reliably. This competes with the opportunity cost of using the frame on a 2nd SFO frequency, which can operate with a better payload and offer more connection options (with 2 daily flights at different times). It's the same reason SQ can fly the standard A359 on SIN-SFO but is waiting for the 900ULR for LAX service. 300nm makes a difference, especially that far on the margin.