When we have a job we love, we want to do it as best as we can. If it’s a profession you have been thinking about having when you were little and then went to get an education to be able to pursue that career, you care about finishing tasks and going the extra mile to make sure everything’s done.
The saddest part is that the company didn’t care that they were overworking their employees and didn’t even compensate them properly. The OP said that he received a raise every year which was less than a coffee would cost and when he earned some bonuses, they didn’t look that impressive after taxes. After getting the offer, the OP gave in his 2 weeks notice at his current job as a courtesy and asked if he would be paid his PTO. Over the time he spent at the company, the OP accumulated 80 hours of paid time off but hasn’t used them, so logically, he was expecting to be paid for them.