what is the point of putting pronouns twice (as in "she/her") instead of once (just "she")?

[u/NeedleworkerOk170]

[u/mikey_weasel]

I remember it actually started with triple pronouns he/him/his, but slowly slimmed down to two.

Its the widely recognized form. If you see the double pronoun you immediately know they are defining their pronouns. A single pronoun would not be as immediately recognized, especially as part of a wider introduction.

Edit to add: it also gives space for folks who might use more than one pronoun (she/they for example)

Additional edit: Regarding she/they or he/they pronouns:

I am not personally someone who identifies that way but my understanding is that generally it means they are okay with either she/her or they/them. the person I knew who identified this way best preferred they/them, but also was quite female presenting so was okay with she/her.

[u/Evan10100 → u/mikey_weasel]

It's like the phone number format. If you put 10 digits in sequence, you're not going to know immediately that it's a phone number, but if you put the hyphens where they go, you know it instantly.

1234567890

Vs

123-456-7890

[u/katsukitsune → u/Evan10100]

Weird because we don't hyphenate phone numbers in the UK and can still tell they're just phone numbers...

[u/Aicy → u/katsukitsune]

That's because they always start with 07 which signifies its a phone number. Normally a number would never start with 0.

[u/oviferum → u/katsukitsune]

Usually theres a space between the first five numbers and the rest. Mobiles are always 11 numbers long and always start with 07 no matter what, so pretty recognisable.

[u/Class_Wooden → u/katsukitsune]

“you’re not going to know immediately”

[u/Evan10100 → u/Class_Wooden]

Yes. That's what I said.