What argument will you employ?

Being the boss is less painful

"If you're worried about spankings, I'd've thought being the boss would be a lot easier on your bottom, even if you are a bit inexperienced," you say.

"Oh, no, sir—I mean Jack. I'm not trying to avoid spankings. The more I get thrashed, the quicker I learn, so waiting for my promotion will probably mean I'll be capable of being the manager sooner than if I took the job right away."

"Aren't you getting punished for different things, though? I don't know how transferrable the skills are. There's not much point in waiting if you still have to learn from scratch when you do take up the position."

"Well, actually, the existing manager has been grooming me for a while. He's been letting me basically do the job under his supervision and then giving me a really strict flogging at the end of the shift for anything he sees me doing wrong which wasn't picked up during the day. I'm getting the experience I need and being punished for mistakes that might get missed if I were already in the top spot."

You can't really argue with that, but it does bring another question to mind.

"Doesn't he think you're ready, then?"

"Um, yes, he actually recommended me for the post, but I'm still getting caned so often when I'm acting manager that I can't really be up to the standard required, yet. I think he's punished me for something every single time he's let me do his job for him."

"That must be expensive—unless he has you tip him with sex every time," you observe.

"Oh, it's always sex. In fact, ever since the tipping rules came in, it's always been sex for me, or menial work. I've never given a single monetary tip, for some reason. Weird. Anyway, as humiliating and degrading as it is, I'm very grateful for the tipping rules, because it was just after they started that my boss suggested training me to take over after he left."

Well, that explains why he's so keen to find fault. You're a bit surprised he's moving on. His new position must offer something special to outweigh having the competent Tilly do his job for him, use some excuse to flog her over his desk and then have her pleasure him expertly whenever he feels like it. Still, it doesn't help you.