Absolutely not the flight attendants: they are the ones who really decide if you will get an upgrade on the flight

According to simple flying, ground handlers and flight crew often rely on algorithms that indicate which passengers have priority for an upgrade. Thus, most upgrade decisions are made by automated systems, including software powered by artificial intelligence such as Saber Upgrade IQ, long before boarding begins.

The various airline systems continuously evaluate and rate passengers based on status, how much they paid, what upgrades are left, their flight history and many other factors. These systems automatically process all the considerations and rank passengers according to established priority rules.

Even before the flight, the systems mark potential passengers who can receive an upgrade and only after that, during the check-in process at the airport and sometimes even with a message to the phone, the representatives of the airline begin to manage the various upgrades, assuming of course that there are available seats in the luxury classes.

Therefore, passengers who emphasize personal charm, appearance or personal interactions at the airport, are indeed doing something very appreciated, but not necessarily increasing their chances of flying business.