Drag - Adjustment - Spin Down

[simonk1967]

Hi,
I am trying to understand what is adjusted internally to a turbo trainer after a spin down/calibration
As far as I can understand it adjusts the drag of the unit.

But trying to work out,
If I do a session on the turbo trainer then perform a spin down and it calculates a value of say 22300 milliseconds
Then do another work out and it gives a value of 20000 milliseconds

Does that mean the drag was too high or too low.
(I’m trying to figure out if the spin down is lower it means it will be easier to put out 200 watts next time or it will be harder ) ?