Why doesn't repeated change div'a (block)?

Hello. Here is the link for clarity.
The first question: in Fact, specified in the title of the post (for clarity, when you click on links, click on the second or third div)
The second question: On a scale genocides such lines will take the first place? (joking of course)
June 14th 19 at 20:58
1 answer
June 14th 19 at 21:00
There are only assigning the value off always happens

Here is my example of this
https://jsfiddle.net/d2Lf74nw/
Why? line
$(".for").text("on "); // need to reset all the divas and put them on
after that
$(this).text("off first"); //set off for the clicked element - etha23 commented on June 14th 19 at 21:03
So you when you assign and remove span
And after writing on nowhere - Fredrick commented on June 14th 19 at 21:06
Sure! Thank you! - etha23 commented on June 14th 19 at 21:09

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