To add more to Enrique's explanation, here is an example from my experience.
I have a column in which I entered time in IST
IST -------- 2:00 AM
And when I get the value of this column,
var myTime = range.getValue();
who actually came back
Sat Dec 30 1899 01:36:40 GMT+0530 (IST)
But range.getDisplayValue () solved my problem, which returned what I entered at 2:00 in the morning.
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