I have found that the system's response to a merger proposal is not consistent.
Sometimes when I propose a merge (where I am one of the managers) I will directly get a screen that says "Thank you for your approval for this merge...." so I can proceed to other matters.
Other times, I get the screen that says " The approval of the managers is ... etc." In this case, if I do not want to have this merger need action by me later, it is necessary to propose the merge a second time, whereupon the approval screen shows up.
I have mentioned this before, but do not have any idea why it happens. Could be as simple as whether "my" profile is in the right or left half of the screen, just don't know.