From: Planning the end of the world, well out to 2023!
To add my bit of Rommel bashing
There are a number of factors involved in the Afrika Korp's (and the Italian's) ultimate failure: Some of the key ones are listed below in no particular order:
1. Rommel did not obey orders. His original purpose was to stabilise the situation and stop the Italians from being kicked out of North Africa. But as Alfred outlined above, Rommel wanted to do what Rommel wanted to do. Because of his initial success, Hitler indulged him. It was a mistake.... unless Hitler decided to commit to the theatre, I'm not sure 2 more Divisions would have been enough, but a proper commitment in the air and on land was needed. Hitler was more concerned in clearing out the untermensch than having a strategic view of the Med.
2. Having pushed the Italians all the way back to Tripolitania, the British made the error of trying to help Greece - thus taking troops away from North Africa and allowing Rommel to advance into Cyrenaica. Rommel was lucky, the bloody mindedness of Churchill et al to go back to Europe in 1941 via Greece saw the 2 best Commonwealth Infantry Divisions squandered in a theatre where they had no chance of winning. Rommel then moved into a battlefield where the best infantry and armour had been stripped out and replaced with barely trained Australian Infantry & British Armour. IMHO Rommel would have got pushed back if the Australian 6th Div, New Zealand Div and British 1st Armoured Bde had been at hand. Australian 7th Div was at hand and I think if this scenario took place would have been added to the available force.
3. Rommel never had enough men, and in particular material, to finish the job he wanted to do. When things turned sour in the Soviet Union he was always going to be struggling for both. Even had he been given more panzers, supplying them was always the problem. He even planned at times to survive on capturing supply from the Brits, and only pushed onto Alamein using supplies captured at Gazala and Tobruk. Even if the supplies were in theatre, Rommel didnt pay enough interest in ensuring they got to the front efficiently. Maybe handling the Italians better might have seen a better result.
4. The more he achieved (in pushing back the Commonwealth forces), the longer his supply line became. Almost everything had to go to Tripoli and then be transported to the front. That used up a good deal of the petrol - and wore out his trucks - that had been carried over even before it got to his panzers.
5. The Royal Navy was a pain in the butt and ensured supplies received were somewhat less than that expected - particularly in late 1941.
6. The Aussies, British and Poles proved a thorn in Rommel's side with their defence of Tobruk. This stubborn defence meant Rommel could not advance. That the Aussies were barely trained and the British Tankers the remnants of a smashed force shows how Rommel could have been so easily repulsed by a better equipped XIII Corps/8th Army
7. Malta should have been taken. Yep, even in preference to Crete. Malta controlled the Med, Crete just the Eastern end.
8. Ultimately the biggest error was repeating France's mistake in Spain in 1808-1814 i.e. North Africa was an unnecessary diversion for the Germans while they were engaged in the real struggle against the Soviet Union, while for the British, North Africa gave them a chance to fight - and whittle down - and learn how to fight - the enemy. Ultimately the Commonwealth and later the US Army would have more troops, tanks, guns and aircraft to bring to the theatre.
Interdum feror cupidine partium magnarum Europae vincendarum