What suprised me about thesis staements

Today when we were picking out thesis statements and putting them in order of gold, silver, and bronze, I noticed that most the gold thesis statements not just had a point, but they had an explanation as well. There were a few short thesis's but they were so clear you didn't have to explain. I guess it depends on what you are writing about or how you state your thesis? I just started writing proper university style essays, it is very different. I have learned a lot about thesis statements today, and it will give me helpful tips in writing by doing this exercise.