Why does "the bat" create additional tags?
The Bat! Professional Edition
v- 8.5.8 (64)
Original tag set - https://imageshost.ru/images/2018/08/09/00.png
1. The user received a letter.
2. The user for the letter has installed the tag "АВ_ТЕГ" - https://imageshost.ru/images/2018/08/09/01.png
https://imageshost.ru/images/2018/08/09/02.png
3. The user writes the answer.
https://imageshost.ru/images/2018/08/09/04.png
4. The user fills in the tag "АБ_ТЕГ".
https://imageshost.ru/images/2018/08/09/05.png
https://imageshost.ru/images/2018/08/09/06.png
5. The user sends a message.
6. "the bat" I sent the letter.
7. The user goes to the "Sent" folder.
A "sent" letter has an incomprehensible tag
https://imageshost.ru/images/2018/08/09/07.png
As a result, "the bat" created several tags
https://imageshost.ru/images/2018/08/09/08.png
https://imageshost.ru/images/2018/08/09/09.png
https://imageshost.ru/images/2018/08/09/10.png
Question.
1. Why are additional tags created?