But, what is surrender? When do we not surrender?
When the mind is full of Ego - surrender is impossible. Surrender, in fact, is, of our Ego in total. When failures occur, the ego takes a beating. Surrender is possible then too. When successes occur, and when we see, that our failures and successes are not totally due to us, that the superior force of almighty is always at work to reward our effort adequately - surrender or samarpan becomes possible.