dissimilarities in area values - raster / terra/ GRASS

[Ohm-Np]

I have done area comparison for a polygon using grass, raster functions - from branch master & terra functions - from branch terra and found some dissimilarities in the result as you can see in the table.

Area of polygon: 1094.880915 sqkm

WDPA_ID	name	value (grass) sqkm	value (raster) sqkm	value (terra) sqkm
6675	area_2001	997.573036	126.3151016	126.4386520
6675	area_2020	872.536478	21.0387268	21.0594864
-	-	-	-	-
6675	loss_2002	0.762019	0.7674429	1.3987885
6675	loss_2019	8.174405	8.178824	0.5946693
6675	loss_2020	21.054441	21.03873	8.1867638

The area from raster and terra are almost same but the area from GRASS seems reasonable. However, the loss value is similar for GRASS and raster. For terra, it might be error in subtraction from my side while computing loss as I didn't use lossCalc function.