i just turned on a customer's laptop for the first time in months. the battery was completely drained, so i had to find & plug in their charger. after the laptop powered on, windows immediately logged off & shut down.

why?

because the laptop lid was closed right after the owner clicked on shutdown. windows stopped the shutdown & went into sleep mode instead, so it didn't finish shutting down until today, & it stayed in sleep mode until it drained the battery.

default windows behavior.