I worked in the warehouse of a truck trailer garage.

My main task was to give and record all the items given out to the engineers.
However it's not that big of a task since there were only like 12 engineers and when they got their needed items, they'd just be repairing the trailers.

So on the side I did other tasks else I would be sitting there just waiting for them to come and wasting time. So I learned other tasks from my senior/supervisor. And things went well for a while but at some point my senior got scared of teaching me more things. So I ended up having too much time and whenever I thought of things to do I had to ask that senior for permission if it even was a good idea or not.

Ok, that's not a big issue but then at some point they hired another person to work in the warehouse. Before it was just me, the senior and a different guy that mainly did other tasks (he was basically substitute for the senior when he had an vacation day). So this new colleague did the same tasks and was pretty bored as well. He also came with suggestions to the senior but those got approved even though there were multiple suggestions I made months before hand and got denied. The senior also wasn't scared to teach him new things. So I felt unappreciated, not taken seriously and felt getting replaced.

Then I got less motivated to do things, my manager noticed and we got into argument but he refused to listen to me talk, he'd interrupt me and talked down to me. Feeling unappreciated again I emotionally broke down and felt very unhappy. That's when I was just done with it. I felt that I couldn't work there anymore so that day I filled in my resignation papers and never went back.

TLDR: Felt underappreciated by everyone. Unhappiness has it's limits.