Heracles is best known as the strongest of all mortals. Stronger then many gods. So strong he was the deciding factor in allowing the Olympian Gods to win their battle with the giants. He was the last mortal son of Zeus. He is the only man born of mortal woman to become a god upon his death.
Offsetting his strength was a noticeable lack of intelligence or wisdom. Once when he became too hot he pulled his bow out and threaten to shoot the sun. This coupled with strong emotions in one so powerful frequently got Heracles in trouble. While his friend and cousin Theseus ruled Athens, Heracles had trouble ruling himself. His pride was easily offended. He took up grudges easily and never forgot them. His appetites for food, wine, and women were as massive as his strength. Many of Heracles great deeds occurred while doing penance for stupid acts done in anger or carelessness.
It would be easy to view Heracles as a muscle bound buffoon. Indeed, many of the comic Greek playwrights used him this way. Even among serious critics he was often seen as a primitive, brutal, and violent. There is much to support this view. His chosen weapon was a massive club. His customary garment a lion skin, head still attached. He impiously wounded some of the gods. He threatened Apollo priestess at Delphi when a answer to his questions was not forthcoming. He created most of his own problems.
However, Heracles as simply a macho buffoon is unfair. If he held grudges, he would also do anything to help a friend. Once his anger passed he was the most critical judge of his own actions. He was too strong for anyone to force a punishment on him. That he willing did severe penance shows a fundamental sense of justice. During his punishments he shows patience, fortitude and endurance that are as heroic as his strength. Terrible things happen to him because of Hera's hatred, a hatred that he is not responsible for. That he perseveres through it all is a moral victory beyond simple strength.
The view of Heracles shifted considerable over time. The early view focused on how badly he managed despite his obvious gifts. As time passed the focus shifted to his virtues. The Romans valued him highly as he best fit their idea of a hero. He eventually had a fair sized cult that worshiped him as a god.