[Tactic]

It depends upon how one defines success. If you mean Bill Gates or The Beatles level success, I will agree that luck plays an integral role.

If you just mean a successful career that takes care of your needs and much of your wants, provides for a comfortable life and a family, I would argue motivation, dedication and skill play far larger roles.

In fact I would say extreme success requires some extreme good luck, whereas a more "standard" success requires good luck less and is more about not having bad luck to counter your abilities.