Sometimes, we hear people saying that they regret doing something (especially when they see the results of their actions). These commonly happen when things become worse after their actions. Nobody would say "regret" if good things happen to them.
Something that seems good in appearance doesn't mean that it's really good inside. And something which is not good in appearance maybe something good in disguise. Let me tell you a story that happened in China long ago. This is probably known by many people.
Long ago, in China, there was a young man, who found a horse at a field. He happily rode it back to his home and told his father about it. They were very happy since horse was quite expensive and they were poor that time.
Not long after that, the young man rode the horse out. A few hours after that, someone informed that young man's father that his son (the young man), fell down from the horse and broke his legs. He thought that the horse had brought them misfortune.
Their country was recruiting new young men for being soldiers at that time. And the king made a new rule that all young men should become soldiers for their country. Of course, everyone knew that it's hard to come back after going to war field. But when their family was asked for young men, they fortunately excluded from this obligation because of his son's broken.
A few months later, the war ended but the news of no survival back to hometown, had proven to the family that they were fortunate enough because their son was not selected for being a soldier.
So, remember that something you call "misfortune" could be "fortune" in disguise.