ML Image Classifier not giving expected results on simulators

Symptom

I created an Image Classifier app, “Chichibu Unkai Watcher”, and it returns right results on a real iPhone device. Also it returns right results on mac catalyst. But, I found that the iPhone/iPad simulators do not return expected results.

XCode Version 13.1 (13A1030d)
Simulator Version 13.1 (970)
Create ML Version 3.0 (78.6)

Fig.1 iPhone real device: Unkai confidence level is ~0%.
Fig.2 mac app on macOS Catalyst: Unkai confidence level is ~0%.
Fig.3 iPhone Simulator: Unkai confidence level is 69%
All of those are using a same image data, and the Unkai confidence level should be ~0%.

Discussion

I tried some GPU settings on the simulator app, also some compiler settings changes, but it does not resolve this symptom. I found an article on the Stack Overflow which says it might be caused by the simulator. At this moment, I’m assuming this is caused by the simulator.