Do over the years I have done many jobs, obviously the short term stuff isn’t on my CV and nobody knows! 
Breakfast waitress aged 16 in a 4 star local hotel. Left after a month. The breakfast supervisor wasn’t very nice and somebody else who worked there (same age as me!) lied to me about my rota dates and the supervisor rang me at home to ask why I wasn’t in and was really snippy with me so I resigned! The other staff were very bitchy too. They have a Starbucks in the hotel now so on the rare occasions I go in for a coffee when at my parents - I see them - still working there! Not that they recognise me. This was years and years ago too!
Working on the hospital bank whilst a nursing student, I only did a few shifts before switching to the clerical bank. I had a horrible shift when a patient shouted at me and I walked off and didn’t go back. It should have been a sign that nursing wasn’t really for me!
Medical secretary in a private hospital. I quit after two weeks. The practice manager wasn’t very nice and the other med secs were very snooty and much older than me and weren’t very friendly.
PA at the HQ of a huge bank at Canary Wharf. I hated how corporate it was and how unfriendly the other people were. Left after 3 months.
PA to Directors at the HQ of a rail company. They expected so much and the PA training me was nasty.
Compliance Administrator at the HQ of a financial company. Good money but I discovered compliance is really dull and nothing was really sinking me - lots of Excel spreadsheets. The girl training me wasn’t very encouraging or pleasant. Left after 2 months.
I had an internal move in the Civil Service to a project planning and scheduling role. It involved lots of training and again lots of Excel and nothing seemed to click. I then got a move to a different job role. The funny thing was, whilst waiting to move to a different job the team I was training in didn’t want me. So I spent two months “working from home!”
Temping at a council office. I was executive assistant to a bitch of a director. I walked out one lunchtime after 4 weeks and never went back!