I think there's a bare minimum you can prepare when things are crowded. Like have milk heated up. Have blenders ready to go. Optimizing those milliseconds to poor waste down the drain is missing the plot, stereotyping and empathy topics aside. Your "prediction game" turns into a business liability.

I worked as a batista 20yrs ago and used to play these kind of maximum efficiency mindgames too, I get it. You get in the zone and it's like a dance on autopilot. You should consider working in software or process automation, side note.

Re empathy and customer service, if you know the customer, sure why not. I always order the exact same drink at the exact same places, and I appreciate my drink being ready quickly. Feels like a perk of customer loyalty. If someone knew my drink before I asked for it, that's profiling. It's creepy. And if it were too fast, I would probably think this coffee shop is pawning off a wrong drink on me. It's untrustworthy. (Split shot Americano with a fee ice cubes and splash of creamer, btw).

All this to say, take those extra seconds in your flow and maybe smile at customers. Or chit chat with colleagues to rebuild some trust you've lost by coming off arrogant and racist. There's better uses for that time save, for you and for everyone. It's not a bad thought process, but if you can't zoom out it's a problem.

Optimization doesn't mean only time. There's bigger measures of success in this equation too, customer satisfaction (and creepiness), team dynamics, inventory replenishment rate, etc etc etc.