Serendipity is literally called unexpected good luck. It’s hard to describe serendipity without involving luck. They are saying that the difference between the two is that luck is unexpected and it can be good or bad. Meanwhile serendipity is just good. There’s not a lot of that in my life, no.
There is no way you one can disassociate serendipity from luck. It is usually an unexpected discover of something of value, hence luck contributed to a large extent. I can remember that there was a time I had an argument with my friends about my skills in a particular game. The disagreement was tense, and we had to go to a betting center to prove our skills. Before that time, I had no intention to gamble. During the process of our skill test, I was lucky to win big.