The hero is not over cautious, he is a control freak. Imagine you make an extreme control freak as a hero for your story, yeah it is that bad. In return, the goddess is too carefree. This leads to many tragedies since the carefree attitude puts them in danger, which increases the the extreme of control freak of the hero. The goddess also never reflects on her mistakes which makes her annoying, which is bad because she is the MC as well. If that keeps happen, the control freak may reach its peak and explode, which is also in the novel in later chapter. From then on, it is very hard to keep reading because now both the MC is bad. Ofcourse, they have the side characters to balance the atmospheres and the tones, but with poor execution, both MC still leaves a bad taste to the readers, explaining why people keeps ditching this novel.