> But there is also bad QA: The most worthless QA I was forced to work with, was an external company, where I, as developer, had to write the test sheet and they just tested that. Obviously they could not find bugs as I tested everything on the sheet.

This was my sole experience at the one place I worked with an internal QA team. They absolutely could never find bugs that devs missed, often mis-marked ones that didn't exist, and failed to find obvious edge cases that did exist.

Multiple devs fired because the CEO believed the QA over the engineering team; if they marked a bug as present, it was the engineer's fault for writing it. If they didn't catch a bug that made it to prod, it was the engineer's fault for not including it in the test plan. They represented nothing but red tape and provided no value.

Good QA sounds great! I'd love to know what that's like someday! It'd be great to have someone testing my code and finding breakages I missed! I'm only slightly (incredibly) bitter about my bad experience with its implementation.

I do think the type of testing where QA just follows pre-generated script has place. But it is about long term regression. The first round absolutely should not find anything. But with complex system it also should find nothing in a year or three or five years... Offloading this to dedicate resource could be useful in certain industries.

Not really that impressive, that's Testing Quick Attacks 101