[Suicide Junkie]

What I mean, is that they are stored as a partially completed defense project.

If the enemy has one Intel defense III, thats 300,000 points to complete. Since the enemy in this case, generates 10K per turn, on turn #20, he has 200K out of 300K on his defense project.

When you try to hit him with a ship capture or whatever, you may spend 40K in one turn.

That 40K is subtracted from his defence.

On Turn #21, The enemy now has 200K -40K +10K
=170K out of 300K on his defense project. His defense held, and your attack failed.

After 7 turns of this, the enemy runs out of defense points, and your attacks start to succeed.