I did not say it was all luck. I said if any part of the outcome depends on luck, effort is meaningless when it come to the result. This is not to say that doing nothing is better, I am just being realistic.

But even going with your examples, effort isn't "meaningless", it's insufficient.

I might have misunderstood as english is not my native language but the 100% doesn't sit right with me in the original sentence.

In general I feel people downplay the effects of luck by a lot. My thinking is that the effort is everything but meaningless, in fact it's probably the only thing you can control.