Before someone says
"they lost, so they suck",
lets put things into perspective.
Axis were outnumbered more than 10 to 1 in this war.
For example, USSR alone had population equal to that of Germany, Japan and Italy combined.
Japan, Italy and Germany had population of about 190 million combined.
USSR alone had 170 million.
China had 500 million.
USA had 130 million.
Britain had 40 million.
France had 40 million.
Korea had 20 million.
Thats already over 800 million people, when we disregard the fact that most of the remaining world was also fighting against Axis.
Axis powers were also weakened before war itself.
Allies had huge head start.
Germany had to pay debt after WW1, which caused economical crisis.
Hitler inherited a bad economy and virtually no military power, but he managed to build Germany into superpower in just 7 years.
So when Hitler came to power, he had no military while USA, Britain, France and USSR were already all superpowers at that time.
Japan was a feudal country before Meiji, but at that time USA was already an industrial power. People in Japan were unwilling to industrialize. Most were illiterate.
Meiji turned Japan into military superpower quickly, but USA had huge head start over Japan and much greater amount of resources, and after Meiji Japan didnt have much time to catch up to USA.
In a strategical sense of total war, Axis powers had virtually no chance of winning irrelevant of what strategy they used.
They had much less population, much less territory, much less colonies than allies had and therefore had to have much less military production and military troops than allies as a result.
Axis also had worse trade paths, as Germany and Japan were very far from each other and couldnt unite.
Still, they managed to cause many defeats to allies.
Allies lost entire France in six weeks.
Most of Europe was taken by Hitler.
USSR lost 25% of its territory and lost 10 million soldiers.
Britain was completely overpowered by Germany and pushed out of France and was fighting defensive air war on its own territory despite all the help from USA.
USA suffered huge defeats against much smaller Japan, which had almost no loses in first year of war and had victory after victory, and conquered Korea, China, and many other countries of Asia.
USA even refused to directly invade Japan, because the cost of invasion was calculated to be over 1 million soldiers.
So despite Axis being outnumbered more than 10 to 1 and having huge disadvantage in territory and allies having huge head start over them, Axis powers, thanks to their knowledge of war, have caused serious losses to allies.
These were their strategies:
1. Kamikaze
Japanese strategy
A strategy where soldier does suicidal attack on enemy, destroying himself to destroy enemy.
2. No Retreat Policy
Japanese Strategy
No retreat policy caused great problems for allies, because the only way to conquer territory was to find and kill all enemies, because Japan military always refused to abandon their positions and defended every inch of territory till death.
3. Militarism
German and Japanese strategy
The country is focused on creating greatest military possible using all available resources, hence the term militarism.
4. Blitzkrieg - Lightning War
German strategy
This strategy involves fast, overwhelming attack on enemy, where huge army and huge number of tanks and airplanes are sent quickly, all at once, concentrated to destroy enemy in huge number of attacks happening at once.
5. Attacking first - Surprise Attack
German and Japanese strategy
A very successful strategy which gave Axis victory after victory in early war, because it caught allies unprepared.
6. Total War
German and Japanese strategy
Entire country and all population is expected to support war by military production or fight in war or defend territory against invader.
7. Territory Expansion - Imperialism
German and Japanese strategy
It says to always try to expand your territory to foreign territories before enemy captures them.
Japanese Imperialism also says to make consistent quick great attacks to destroy enemy completely.
8. Technological advancement
German and Japanese strategy
Investing a lot in technology to gain edge in war.
9. Military Risks
German and Japanese strategy
Making risky moves to gain advantage in war, due to such risks carrying reward in most cases.
10. Experiments
German and Japanese strategy
Both countries made lots of experiments in military strategy and technology, which in return gave them better knowledge of strategy and technology.
Germany made first jet planes, for example.
11. Totalitarianism
German and Japanese strategy
While other countries were vunerable by politics, German and Japanese totalitarianism enabled quick decision making.
12. Indoctrination
German and Japanese strategy
Lots of propaganda in media and education was used, and population was made obedient and willing to fight as a result.
13. No surrender
German and Japanese strategy
Determined to fight till end to drain enemy, despite being far outnumbered in Europe, Germany caused heavy losses to allies when they invaded it due to refusing to give up.