Trying to play allowing losses is horrible

[Totoro]

If the game is possible to finish without losses on hardest difficulty it can be challenging for those who strive for no-losses but too easy for good players who don't care about it.

I don't think no-loss concept is good for those who play on its rules either, because when you've finished no-loss on impossible, there is nothing to look forward to.

If losses were inevitable and they would count to score, you could always try to improve your score by avoiding even more losses which would be much less stressful than trying to improve your score by finishing the game in fewer game days.