In the play "Macbeth" by William Shakespeare, the author shows us a man who in some senses is ordinary in that he represents the propensity we all have as beings to "fall" at any obstacle in the path to integrity as a person. In that sense, we are all fallible, except in those days only the Pope and God were infallible, so even a King could be expected to "fall from grace" from time to time, despite the divine right of kings. Macbeth however, seems to have had some extra emotional and psychological baggage to deal with, so that when his "fall" came, he was less able to deal with it, see a way through, stick to a plan and listen to his conscience. His past seems to have left him confused, malleable, irrational, insecure and dysfunctional psychologically. So when things don't go according to plan, his mind and modus opeandi unravel, leading to an escalation of violence.
Concerning Shakespeare's Macbeth, I'm not sure what you're after in your question.
Macbeth is certainly fallible, but that can be said of any character in serious imaginative literature, with the exception of myth or fantasy, maybe. He is fallible--he makes all kinds of mistakes. He is not a god so, of course, he is fallible.
His ambition, gullibility, and lack of intelligence (in some respects) directly lead to the crimes he commits and the downfall that follows them. Any of those words are more relevant to a discussion of Macbeth than his fallibility.
But, yes, he is fallible, and desperately wants the thrown, is easily manipulated by the witches and his wife, and makes extremely poor strategic decisions: he kills the grooms, orders the killings of Banquo and Fleance, and the slaughter of Macduff's family. These all cast suspicion on him and lead to his downfall. Had he stuck to his wife's plan, and left her in charge of strategic planning, he might have gotten away with the assassination of Duncan. In this sense, his fallibility leads to his crimes and downfall.