Another angle on this is general reliability and what that does to the experience. I'm reminded of Linus having a moan about poor availability of ECC in consumer RAM and how many errors that get blamed on software are actually down to something happening to hardware but it isn't specifically identified. Plus when you're talking billions of devices even small proportions are significant. Firefox built a memory tester into their bug reporter tool as that 'noise' became a large enough problem for them.