It may be caused by the coin distribution. As we know, the initial coin outputs are all the same 10000 coins each output, and the minimal and maximum coin days for minting is 7 days. We can imagine there are too many “stakers” with 10000 * 7 coin days owning the same probability are competing the next block. So orphaned blocks is not strange. As NSR distributed and time goes on, there will be more outputs with more than 10000 coins and imbalanced coin output distribution will be achieved, it’s expected a low orphan block probability.
