Cancellations are pretty common in Japan. though there is some rumour about publishers not wanting to publish manwa's beyond the 10th volume may have come from the breaker and perhaps other sequels.
True, but Manhwa cancellations do seems especially high, at least in most of the ones I've read. Crotica which I had just finished recently was another one that just stopped abruptly. So, far ID, and Legend of Tyr look to be one of the only few long manhwa I am reading.