When I left my old job, a lowly shipping/receiving guy in a warehouse, my job panicked and offered me a pretty significant raise if I stayed.

After having been there about 5 years, I'd made myself somewhat indispensable, they kind of just kept piling responsibilities onto me, I absorbed a lot of a supervisors duties when he retired with no replacement hired for him, I had fairly minimal oversight and was mostly left to figure out how things worked on my own (which I didn't really mind, it made the job more interesting and I was up to the task, but I definitely didn't get paid nearly enough for the work I was doing) so I was pretty much the only one who knew how all of our shipping and receiving stuff worked.

Along the way I wrangled myself a couple OK raises, but not really enough to bring me to a proper living wage. I had asked a couple of times about at least getting a promotion in title if nothing else so that I would have something more impressive on my resume that "warehouse associate" which I'm pretty sure was my job title the entire time I was there despite effectively being a supervisor.

When they offered me more when I told them I was leaving, it pissed me off more than anything. If they'd just paid me that much from the get-go and kept on top of giving me decent raises to reflect the job I was doing there's a good chance I'd still be working there now and never would have tried looking for another job. What they offered me wasn't quite my starting salary at my new job but it was pretty close.

I could have left them really high and dry and just left, but I didn't want to screw over whoever was replacing me too badly, so I wrote down instructions for everything I could think of that was my responsibility because honestly no one else had the whole picture, a handful of people there could do parts of my job but a lot of it, like I said, was stuff I had to figure out on my own. All of the business cards I'd acquired for different shipping companies, vendors, etc. and I gave 3 weeks notice and attempted to pass on as much knowledge as possible to my likely temporary replacement before I left. Last I heard, they went through several replacements within a few months of me leaving.