Luck can be relied upon only after it has happened.
Those who rely on luck stand on slippery ground. Luck is one of those things that is retrospective in nature only. It therefore does not really exist in the present, which is the temporal domain that all life inhabits. As such, the concept of luck really should have no place in any decision a person makes in the present. We can comment that someone has experienced luck in the past, but no attempt should be made to apply such fact to predicting either present action or anticipated future outcomes for that person (even if that person is you). If you decide to take a chance on something, know exactly what it is you are doing—taking a chance. Luck plays no part in whatever happens. Your odds of success will likely follow the laws of probability and will be influenced by the degree of preparation and/or skill you bring to the endeavor. Why not simply expunge the word entirely from your vocabulary? It really has no practical use in our existence.