Inside almost every arcade cabinet is a Dell Optiplex running Windows 7, or 10 if its really recent. There’s no such thing as an arcade board anymore, they’re all Dells, or sometimes those HP mini PCs, usually with the protective plastic still on.
Daytona even uses a Raspberry Pi to control the second screen. SEGA intentionally ships those with no-brand SD cards that consistently fail after 3 months. It’s in their agreement that you’ll buy another card from them instead of just flashing the image onto an SD card that won’t break.
The Mario Kart arcade cabinet uses a webcam called the “Nam-Cam” that is mounted in a chamber with no ventilation, which causes it to overheat and die every few months, so of course you’ll have to replace those too. The game will refuse to boot without a working camera.
Oh yeah also all arcade games with prizes are rigged. All of them. We literally have a setting that determines how often the game will allow wins.
What is a well known 'public secret' in the industry you work in that the majority of outsiders are unaware of?