Who decides our destiny? Is it our luck or is it our effort? This is a very deep question and there are no simple answers to this. We can easily sit on either side of the equation and can defend it with logic and examples. Though as a society, we preach and maintain that effort is superior than luck as this also maintains the industrious nature of society, but is that the answer.
Let's sit on the effort side. It's very easy to convince that effort is superior than luck. Luck can help you in getting to a pot of gold but your effort will define the success. If you want to pick it up than you will need to put effort.
न हि सुप्तस्य सिंहस्य प्रविशन्ति मुखे मृगाः ।।
Without effort no work is accomplished
The deer does not automatically enters into Lion's mouth.
The literature in all culture is filled with the virtue of doing hard work and right from our childhood we are taught the importance of doing hard work.
Now let's sit on the other side. It's the luck part which decides our destiny. Look back at your life. Did you choose each facet of it? Did you choose where you will born and what kind of ecosystem will surround you, when you are maturing in terms of your habits and attitudes? I would like to put a word of caution here. I am not encouraging to judge the past in terms of good and bad. I am encouraging to look at it in terms of hard cold facts. Nothing more nothing less. In Bhagvad Gita, Sri Kirshna tells Arjun
अहं सर्वस्य प्रभवो मत्तः सर्वं प्रवर्तते ।
इति मत्वा भजन्ते मां बुधा भावसमन्विताः ॥
I am the reason of everything in this world.
Those who understand this, devote themselves to me.
So it's a perplexing question that what is the truth or if there is a truth. The luck side can easily defend by saying that we do effort because of luck. What do you think?
I am not encouraging you to stop working because of this discussion :). Who knows may be the truth lies on the effort side. And I don't think humans will ever learn the true facts. We can assume that we know by putting a complex structure of logic but the fact is that we don't know who is God and who knows the answers of all these questions.