Microcontroller RAM life expectancy
SRAM, DRAM has infinite endurance.

FLASH, FRAM, and EEPROM have limited endurance.

SRAM is made with transistors or mosfets. It's an active component that loses its state when power is removed.



DRAM uses tiny capacitors to temporarily store data, these are continuously refreshed by the memory controller because these capacitors leak. Both DRAM and SRAM will work until material degradation renders the part unusable. (decades)

FLASH and EEPROM work similar, by using capacitive effects on fet gates, and these do have limited endurance. "Flash wear" is caused by erasing due to slowly accumulating charge around the flash cells during erase. When flash is erased, it is erased to a logic 1 by a "high" voltage.

FRAM works magnetically, it also has limited endurance. But the write cycles are in the trillions, almost infinite.