Did you mean to ask what job is unforgettable for you? As in, what job did you have that was an experience you will always remember.
For me it was my first official (taxable) job when I was 15 and worked for the local county at the recreation center and had to pull weeds much of the time in the desert sun. I consistently acted arrogantly as if I was above the position, barely doing what was tasked of me. I conflicted with just about everyone and was always at odds with the people there. I railed loudly against the perceived injustice of me having to pull weeds while the girls that were part of the same youth work program never did, and were able to lounge about inside doing work that seemed to mostly consist of participating in pottery time with the elderly. My boss was herself female and I found the situation patently unfair and biased.
I learned a lot about myself through that, but only much later and with many other corroborating events. It still serves as a sort of snapshot wherein I did everything wrong, considered only myself and my own interests, and ignored every signal that was sent to me. I was completely self-absorbed. Thinking of other people, and putting myself in their shoes was a thought completely unknown to me. I still think I was correct, it was completely biased that they were totally exempt from some duties while I was not. I did everything they did, cleaning toilets, kitchen work, etc. In this case, I was tilting at windmills. The cultural programming of these individuals in that respect was very strong. I had noticed this on their faces when I brought it up, it was very weird that I would even suggest they be out with the men doing "men's work". I saw it completely different, but for them it was simply inconceivable. So I created enemies out of nothing, seeing others as acting against me personally when they were really just stuck inside their own minds, acting out what they had been programmed to do. They really couldn't do any different, and I failed to appreciate that.
But instead of taking a step back from the situation and learning something from it, and choosing what was in my best interest for that moment, I chose to only care about my little I's and what they wanted. My I's wanted to be inside with the A/C, and not work outside in the dry heat. They were/are lazy and didn't want to work, and instead wanted to complain about others and wanted those other people to suffer in the heat with me.