Poor training, poor documentation, lousy equipment, lousy pay, constant emphasis on keeping costs down.
I was hired thru the husband of my wife's co-worker, simple interview. And I was warned at the interview that the pay was going to be a lot less than someone with my skillset would normally earn. But I needed a job, so I did not quibble over pay.
The testing involved following a number of steps (and running some scripts written in a version of BASIC) which required little experience or offered no latitude for further investigation. My primary challenge was memorizing all of the testing process, which involved a number of steps not documented, & forced the tester to rely on "tribal knowledge". The lead's explanation was "The steps change all the time, and if I tried to keep it up to date, I'd end up spending all of my time on documentation."
Three weeks in, I had an informal job review. The lead concluded the meeting by telling me, "Keep on doing what you are doing." Friday of week 6, I was told I was not learning the job fast enough & my services were no longer needed. To say I was blind-sided is to put it mildly.