1. It's the rush period, just like how all of the big blockbuster movies are released during the summer. It's also the same reason why similar stores are built near each other, like a downtown area just filled with restaurants, or another area with only clothing stores. If a lot of girl groups are performing around the same time, there could be more attention and interest towards the idol scene collectively, as opposed to if they individually had comebacks at separate times.

2. Summer means hot weather and shorter clothing. Girl groups can naturally show off their sexy side with slightly more revealing clothing, like short shorts and skirts. Whereas in comparison, girl groups might look more out of place wearing such clothing when it's freezing in winter.

OSEN also added that while the performance and choreography are more important for boy groups, the concept and outfits of girl groups can have more of an effect on their popularity.

3. Artists who have a successful comeback in the summer can reasonably promote for a longer time until the end of the year. And in terms of the chances of winning awards at the end of the year ceremonies, a summer comeback allows for a long enough time period for a song to reach its height of popularity, but not too long that the public will forget about the song by the end of the year.

A representative said, "If you have a comeback during the summer, you can have a lot of events during the fall. At these kind of events, upbeat songs are typically preferred and summer songs usually fit well. For the end of the year awards ceremonies, some artists have their comeback in the fall, but summer is preferred."

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These are the reasons OSEN gave for the summer girl group comeback wave. Why do you think so many top girl groups are making a comeback this summer?