If I leave A with 10000 kg of fuel and land in B with 5000, but my OFP trip fuel is 7000 a question crosses my mind: how comes I saved 2 tons of fuel?
Then I refuel, I ask to have again 10000 kg, so now I read again 10000 on the gages (I had 5000 before refueling, so I should have loaded 5000kg). Now I insert the data in the techlog and xcheck the actual liters versus the calculated and guess what? Seems that I loaded a lot less fuel! Still saving money!
But now the big question: are the fuel gages working correctly? Should I check with the dipsticks?
Just read your manuals (I'm not an ATR driver, but I think there's no difference) and you get the answer. And some more live souls on this planet....