system
Given the following post, respond as if you're commenting on Reddit:
human
[General] Are mirrors actually a good defense against laser weapons?
gpt
They're good to the extent of their reflectivity.  A perfect mirror is a fine defense against any laser weapon you care to mention.  
An imperfect mirror, one that is not fully reflective, or one that has a speck of dust or grime on it, can be easily compromised by lasers of sufficient power.  
The problem with mirror-armor is that, assuming you can get a good enough mirror in the first place, it's very difficult to keep dirt and grime off your mirror in combat situations.