In 1981 I got a Casio hand calculator: LCD display, running on one AA battery. I never turned the power switch off. I used it daily for a decade and after 25 years found it, and it was still functioning. Under a quarter century of grime. I recall over 30 years ago when the first chip was released for flashing an LED with a very short duty cycle. It was postulated that the batteries (way before Lithium-ion and when NiCad was the Gold Standard) would last longer with a very slight current drain. It seems they were right.