My first job was actually nontechnical - I was 18 years old and sold premium office furniture for a small store in Munich.
I did code in my free time though (PHP/JS mostly, had a litte browsergame back then - those were the days), so when my boss approached me and asked me whether I liked to take over a coding project, I agreed to the idea.

Little did I know at the time: I was supposed to work with a web agency the boss had contracted to build their online shop. Only that he had no plan or anything, he basically told them "build me an online shop like abc(a major competitor of ours at the time)"

He employed another sales lady who was supposed to manage the shop (that didn't exist yet). In the end, I think 80% of her job was to keep me from killing my boss.

As you can imagine, with this huuuuge amout of planning and these exact visions of what was supposed to be, things went south fast and far. So far that I could visit my fellow flightless birds down in the Penguin's republic of Antarctica and still need to go further.

Well... When my boss started suing the web agency, I was... ahem, asked to take over. Dumb as I was, I did - I was a PHP kid and thought that Magento, being written in PHP, would be easy to master. If you know Magento, you know that was maybe the wrongest thing I ever said.

Fast forward 3 very exhausting months, the thing was online. Not all of it worked yet, but it was online and fairly secure.

I did next to everything myself, administrating the CentOS box the shop was running on, its (own) e-mail server, the web server, all the coding required for the shop (can you spell 12 hour day for 8 hour pay?)

3 further months later, my life basically was a wreck, I dragged myself to work, the only thing I looked forward being the motorcycle ride home. The system worked though.

Mind you, I was still, at the time, working with three major customers, doing deskside support and some admin (Win Server 2008R2 at the time) - because, to quote my boss, "We could not afford a full time developer and we don't need one".

I think i stopped coding in my free time, the one hobby I used to love more than anything on the world, somewhere Decemerish 2012. I dropped out of the open source projects I was in, quit working on my browser game and let everything slide.

I didn't even care to renew the domains and servers for it, I just let it die without notice.

The little free time I had, I spent playing video games and getting drunk/high.

December 2013, 1.5 years on the job, I reached my breaking point and just left, called in sick at least a week per month because I just could not see this fucking place anymore.

I looked for another job outside of ALL of what I did before. No more Magento, no more sales, no more PHP. I didn't have to look for long, despite what I thought of my skills.

In February 2014, I told my boss that I quit. It was still seven months until my new job started, but I wanted him to know early so we could migrate and find a replacement.

The search for said replacement started in June 2014. I had considerably less work in the months before, looks like he got the hint.

In August 2014, my replacement arrived and I got him started.

I found a job, which I am still in, and still happy about after almost half a decade, at a local, medium sized ISP as a software dev and IT security guy. Got a proper training with a certificate and everything now.

My replacement lasted two months, he was external and never really did his job - the site, which until I had quit, had a total of 3 days downtime for 3 YEARS (they were the hoster's fault, not mine), was down for an entire month and he could not even tell why.

HIS followup was kicked after taking two weeks to familiarize himself with the project. Well, I think that two weeks is not even barely enough to familiarize yourself with nearly three years of work, but my boss gave him two days.

In 2016, the shop was replaced with another one. Different shop system, different OS, different CI. I don't know why and I can't say I give a damn.

Almost all the people that worked at the company back with me have left for greener pastures, taking their customers (and revenue) with them.

As for my boss' comments, instructions and lines: THAT might not be safe for work. Or kids. Or humans in general. And there wouldn't be much left if you put it through a language filter...

Moral of the story: No, it's not a bad thing to leave a place if you're mistreated there. Don't mistake loyalty with stupidity!

And, to quote one of my favourite Bands: "Nothing matters when the pain is all but gone" (Tragedy + Time by Rise Against).