First I appreciate and wholly support everyone who makes great kimchi here (or even bad kimchi! It’s awesome to try). BUT ALSO please do not leave out your kimchi at room temperature for a week!!
Kimchi is not a pickle. Kimchi is not a science experiment that is supposed to explode. Kimchi is also not an “aged like wine” type food (this is true in specific controlled fermentation, but never at room temperature). That sort of advice being so common here is possibly why I see so many pictures or rotten or moldy kimchi, many of them in conditions that I’ve literally never seen in my 30+ years of life eating kimchi.
Kimchi and the tradition of gimjang is also something that Koreans take a lot of pride in. When Koreans are screaming in the comments saying 5+ days at room temperature is excessive and literally no one in Korea does that, please believe us. Please leave out a batch for a day (or MAX two in the winter—I personally just leave out overnight and no more) and slow ferment in the fridge. If you like mushy brown rotten kimchi personally then I can’t stop you, but please don’t advise others to do the same or suggest that that’s an equally valid, authentic process of making kimchi.
EDIT: I did not expect this to blow up like this and I debated deleting this, but I’m keeping it for now (might delete later). Any criticisms I’m trying to understand as people being invested in their kimchi making process and feeling proud, and then feeling attacked when that method is discredited. This isn’t something I’d necessarily be unhappy about. As someone who loves Korean food and has had a few lunchbox moments myself growing up, I’m appreciative of subs like this and people’s interest/passion in kimchi. Here are a few sources that recommend 1-2 day room temperature fermentation and advise against something longer (~week). (I know people love maangchi here, as I do, and her recipe is also 1-2 days). Ultimately it’s everyone’s individual choices and I’m not saying anything beyond a few days always leads to kimchi going bad. But these are useful guidelines that are faithful to how people locally enjoy kimchi.
https://www.wikim.re.kr/gallery.es?act=view&bid=0013&list_no=2423&mid=a50201010000 (a Korean institution dedicated to kimchi, says deterioration-related surface yeast found to develop in about 6 days at ~70f, not toxic but at this point the yeast has to be removed and the kimchi is not recommended to be eaten fresh)
https://m.kin.naver.com/qna/dirs/8020112/docs/486262557 (a commercial manufacturer of kimchi, says beyond 3-4 days the kimchi tastes off and beyond 7 days it grows moldy)
https://news.kbs.co.kr/news/mobile/view/view.do?ncd=8566851 (school lunch vendors held criminally liable for keeping kimchi at room temperature)
https://kimchi.pusan.ac.kr/kimchi/43688/subview.do (a Korean university’s research—refrigerate after a day for best results)
https://m.kin.naver.com/qna/dirs/50502/docs/467192386 (another commercial kimchi producer, advising against prolonged room temp (recommends a day), “can rot and lead to unsafe microbes”)