Take a look at the electrocardiogram (ECG) below. Maybe, you think that it is normal, but...
You would intuitively feel kind of weird with this ECG, wouldn't you? If so, I think your feeling is right. You have a good sense of ECG interpretation.
Today, I showed this ECG to some young doctors, and none of them made the correct diagnosis although they appeared to think that it was not normal.
After I told them that it was an artificial ECG for the maintenance of a system, they were surprised but soon realized and accepted the answer.
I cannot explain well the reason why the ECG makes us feel uncomfortable but I am sure that it looks weird