Why were tanks useful in world war 2?

Answer 1

Tanks were very helpful to armed combat ground troops who needed the assistance of a huge machine which could sustain many hits, to push through enemy territory and destroy the enemy itself, without causing the death of many ground troops. The survivability rate for tanks was higher than ground troops because they were more heavily armored and had more powerful weapons.

Answer 2

Because they were an efficient weapon to support infantry forces in ground battles, as hand-held anti-tank weapons weren't that common and not very effective. At first, tanks were used as they were faster than infantry and more effective at penetrating enemy defenses and have a good defense. However, Nazi Germany realized that tanks were better if it supported by infantry as infantry could protect tanks from close range attacks and tanks could protect infantry from tanks and enemy machine, and artillery.