I think a developer doing their own QA is far better than them not doing it. How are they not just throwing over garbage if it hasn't been exercised meaningfull

I think a developer doing their own QA is far better than them not doing it. How are they not just throwing over garbage if it hasn't been exercised meaningfully (typically an automated test won't be as good as a manual test but maybe it can be). In the bigger picture, going "slower" is probably better than being worried with "speed of delivery" which then takes longer to actually be done with the level of quality that would make the product "good".