The docstring for org-todo (C-c C-t) is unclear about the handling of - prefix compared to -1 prefix.
Here is the relevant part of the docstring: With ‘C-u’ prefix ARG, force logging the state change and take a logging note. With a ‘C-u C-u’ prefix, switch to the next set of TODO keywords (nextset). Another way to achieve this is ‘S-C-<right>’. With a ‘C-u C-u C-u’ prefix, circumvent any state blocking. With numeric prefix arg, switch to the Nth state. With a numeric prefix arg of 0, inhibit note taking for the change. With a numeric prefix arg of -1, cancel repeater to allow marking as DONE. The actual behavior is that - (along with any other negative numeric prefix excluding -1) switches to the first state and -1 cancels the repeater. It seems like the right fix here is to make - behave the same as -1, and raise a user error for any other negative numeric prefix, since it is likely not doing whatever the user wanted. Emacs : GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.27, cairo version 1.17.4) of 2021-03-26 Package: Org mode version 9.5.2 (9.5.2-gfbff08 @ /home/ionasal/.emacs.d/elpa/org-9.5.2/)