@Mayumi4 As a host, you don't review the guest for the guest's ego or whatever, you review them so that other HOSTS can know what sort of guest the person was. For that reason, you should try to always review every guest, good or bad or in between. You don't have to write a long, personal essay about the guest, but just a few simple facts. Were they well-behaved? Did they follow your House Rules? Did they cause any problems? Did they leave your rental clean or dirty? Most importantly, would you be happy to have them return?
My typical review is 3-5 brief sentences, plus the check-off items. In our case, we truly almost always have genuine 5-star guests. We've only had 1 or 2 mildly problematic (and I mean only mildly) guests in the past year.
Remember: You're not writing the review for the guest's consumption, you're writing it for the benefit of other hosts who might get inquiries from that guest.