Ambition is a state of mind, in some cases it is a good thing, like an athlete that wants it all, but in some cases it is a bad thing, like a young scientist that stops at nothing until he succeeds at his task. The young ambitious scientist referred to above is Victor Frankenstein, the main character in Mary Shelley's Frankenstein. "Ambition: (that which) destroys its possessor." - Babylonian Talmud: Yoma, 86a. It couldn't be put any clearer, because no matter what, ambition can ultimately lead to a persons" demise if not checked. Victor Frankenstein did not check his ambition, he soon regarded his ambition as evil and began to think of his life a cursed by ambition.
Victor Frankenstein regards ambition as evil because it was the driving force behind his ceaseless urge to learn. Because of his ambition he tries, and eventually succeeds, to do the unthinkable, he creates life from death. If it weren't for his ambition his family wouldn't have died miserably at the hands of his creation and he wouldn't have been left by his self to mourn for the rest of his life. The evil of his ambition sent him on a search to find his monster. This search drained every ounce of life from him until he couldn't go on and died. Another aspect as to why he could have regarded ambition as evil is because his creation was ambitious, he wanted a friend to share in his misery and he would stop at nothing until he got that friend, or his creator died. Frankenstein witnessed what ambition could do to someone, in his own life and in the life of his creation.
Victor Frankenstein feels like he has been cursed by ambition. Frankenstein has every reason to feel this way. At a young age, 13-15, he aspires to know all about Alchemy and the powers of electricity. These subjects changed his life forever, they are the founding knowledge behind his creation. While at Ingolstadt, after gaining a reputation as a scientist and innovator among the professors, he decides to take up a new project, life from death.