Difference:
Kpop Idols spend years generally training their bodies and voices to be able to debut. They spend many hours a day doing nothing but training in the hopes that it will help them debut or remain a quality group. Metal musicians most likely don't spend the majority of their day practicing, but they have practiced their instrument to the point where they can be able to perform with perfection.
Similarity:
Both Practice incredibly hard to be good at what they do, and at the end of the day, its all to put on a good show.
GFriend's synchronized dancing
A very technical metal band
Difference:
Kpop performances are full of choreography, so they tend to take up an entire stage with their choreos. They used short films and solo songs to give some of the members a rest. Now, in metal music, there isn't choreography, the artists have to win your attention based soly on their talent and stage presence. As far as set breaks go, there is generally a 10 minute break in the middle of a set. The vast majority of times there isn't something going on in that 10 minutes to distract you, you just have to wait.
Similarity:
Both genres need to win over the audience, they just generally do so by different methods. Their goal for a performance is also the same: to please their fans and to give a good quality performance.
Difference:
In Kpop, there is a much bigger need and desire to know members names because in a performance each of them will be showcased in some vocal way during a show. In metal music, yes, there is still the desire to know names, but (in my opinion) generally the only band members that get attention are the lead singer/lead guitarist.
Similarity:
Both have a severe difference in popularity amongst the members. Generally the main vocalist from both Kpop and metal music are the most well-known or identified.
