Yes, timing and luck contribute to your success. But you also contributed to your success.
One of my early mentors, a long time member of Young Presidents Organization, told me that he and his fellow YPOers had to learn to trust their competence — just like everyone else does.
He taught me that the first time you experience a great success you think, “Whew, was I lucky.” The second time you make it big you think, “Wow, I guess lightening struck twice for me.” It’s only when you make big things happen a third time that you trust your ability and therefore yourself.
Trust yourself; you’re not just lucky. You’re good. Give other people and the gods due credit, but give yourself what’s due, too.