There are many, often contradictory, definitions of success of which the most obvious and in-your-face one is that which hinges on wealth, power and social recognition.
And if we temporarily delude ourself and accept this definition ... then the next question is how does attain this success.
It is very obvious that native ability, basic competence or any other natural attribute, has very little co-relation to success. There are too many incompetent people who are successful and there are too many very able folks who languish in the shadows.
I believe that there are three steps to success.
1] Destiny or Divine Grace : is the first and the most important. In mathematical terms D & D is the necessary and sufficient condition for any success.
2] Perseverance : This falls in the necessary but not sufficient category. A lot of effort, painful effort, goes into the crafting a success story.
and finally ..
3] Unscrupulouness !! .... another necessary but not sufficient condition. To be successful in the material world you just need that little tinge of evil in you, for example the kind that allows you to rough-shod over the feelings of others, or to further your own interests that the expense of your colleagues .. that is what separates the winners from the also rans in the corporate world and in the analogous social world as well.
However  and  can be always be rendered superflous by  which is why we say that career progression finally depends on being at the right place at the right time. Nothing more.
Of course .. if you look at other definitions of success ... then none of these really matter but that is another story