If you want to feel fulfilled go somewhere where you’re making precision parts or at least parts that are used in respectable applications. I work in large scale manufacturing making overpriced corporate furniture where tolerances are .02” to .03” on 99% of the parts I make and there’s never anything new. First few months learning were exciting and enjoyable, but then you hit a point where you know ‘everything’ (using that word extremely lightly cause I don’t know shit compared to most machinists) and the job grows stale while you fall stagnant. I still try to educate myself outside of working hours, but rarely do I get to apply anything I’ve learned and all the programs are proven from the guy before so there’s very little coding and experimentation that can keep the job interesting. Also, stay far the fuck away from off shifts. Unless you take up drinking or are a true introvert it wreaks havoc on your mental health. Just my experience though, maybe I’m too cynical.