Augusto,
Playing the Ai with you as the Germans in the 1944 sceanrio will give you the answers you seek in detail.
Because the Germans are so weak in the air, the USAAF will bomb German oil and heavy industry factories to bits. You may succeed in destroying a large number of bombers and fighters, but it takes few USAAF bombers to do HEAVY damage. As oil and heavy industry totals lessen, your ability to regain readiness will plummet, leaving you few chances to counterattack.
Before long, in the 44 scenario, you find winter arriving, while you build me-262s in great numbers. These fighters begin to wreak havoc on the USAAF and red air fleets, and you think you're about to gain the upper hand. Then spring comes.... USAAF bombers apear in fleets of 500+...and your hopes are crushed, because the USAAF heavies will still keep coming, with some getting through despite astronomical losses.
In these later years...you see that more bombers come in clear weather. In the earlier years...there aren't as many
Jesus ...., with all respect. This closet germanism is allways killing me.