Don’t you feel sorry for the units that die on the battlefield?

The fewer losses, the sweeter the victory.

Maximalism. Perfectionism. It results in rather tedious grinding, replaying the same battle with minimal mana expenditure and no losses.
On the contrary, I enjoy when victory is hard-earned. When you have to use everything you have, overcome challenges, and achieve an epic win. Then you'll have memories of such a situation: "that was awesome." There are fewer such victories than routine skirmishes with neutral creatures using a fairy.
But, of course, it's important to distinguish between a victory achieved at a significant cost and losing troops due to inexperience.