I suppose you meant to say "How it could be possible that such bug wasn't noticed before the release" and I can agree with that, it looks like there's a miscomunication between front end and back end programming, such, maybe some bugs reported in the way the phone handles the memory management have been fixed all while unadvertedly some other component have been let's say corrupted and gone unnoticed after the compiling, then let's say front end has done it's job reporting and back end didn't fixed, or else, front end didn't even do the job and just gave it a go, like I have already experienced with the Xiaomi Mi A2 with the 2020 release that bricked multiple phones. I can't say for sure on whom the responsabiliy falls but I believe the problem should be handled by the whole and hopefully to bring out the problem and fix it now that it's clarified and put to light.
