Simple and straight forward. Why exactly are a majority of dwarf and lich units absolute trash purely because they permanently die? This adds literally nothing to the game, and just restricts the unit options of two of the three races. Nobody can afford to lose thousands of rare resources in a duel or in a siege. Not only is it just plain nonsense, it actually makes no sense that you can't repair mechs, but can heal slaughtered humanoids. On top of that, lich literally have units (mummies) that resurrect dead humanoids as undead, but they can't revive a defeated undead unit? It makes absolutely no sense from a lore standpoint and absolutely no sense from a "did you put any thought into this at all, Devs?" standpoint.
The best part of all of this is that lich probably wouldn't even use anything other than scorp spider anyway, yet the devs refuse to give injury to undead and mechs as if it would somehow be overpowered.