From the article:

It is customary for anyone entering a Japanese home to shed their footwear, and for homeowners to rearrange the shoes of guests or customers to face the doorway so that they can slip them on easily when they leave.

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Interviewed by TBS News Dig this week, firefighter Daisuke Yamashita said, “Emergency crews decide the direction of their shoes according to their roles, so if someone changes their position out of kindness, it can interfere with putting them back on and delay the transport of the patient. From our experience, it can result in a loss of about 30 seconds.

“We do appreciate the kindness behind straightening the shoes,” added Yamashita in the video. “During an emergency, it is extremely helpful if people instead prepare the patient’s My Number card [a social security number] or another form of identification in advance.”

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Another user attracted more than 800 likes for suggesting that strict etiquette could perhaps be forsaken at such times: “It’s an emergency. I would just tell them: ‘Please step inside with your shoes on!’”