Why do I always get defeated by AI so easily?

[dwarftough]

Turn 5, you've formed a defensive line, but it's a line on 40% def. Your leader with L3 leadership is next to L3 units.

My Drakes have 40% almost everywhere. Only Suars have 60%, but they are weak. Do you think I should form this 40% def line near my base?

Turn 7, the Nagas have 0 gold, 8 income and seem to only be recruiting units that cost 27 gold. However, you've got an orc running round your back - I think you'd have won the scenario if the drakes that went for the Naga leader instead secured the west end of your troops.

So with this enemy gold prise after defeating any leader I should just kill enemies to weaken them don't paying attention for leaderkill, right?

Eh, it turns out that my initial plans were wrong as usual, when I've first seen this scenario, I just though " Well, I should quickly and easily shut down Naga with my Infernos to prevent her recruiting, then just defeat waves of remaining foes and to kill them all in an appropriate time". But it happens to be wrong way to do