Yes, it led to more work. What would take half a day could now be done in an hour. So we now had to produce 4x more.
I spent 4 years there automating left and right. Everyone silently hated me. One of the problems with my automation was that it allowed for more and more Q/A. And the more you check for quality issues, the more issues you'll find. Suddenly we needed to achieve 4x more, and that meant finding 4x more problems. The thing about automation is that it doesn't speed up debugging time. This leads to more stress.
One senior guy took me aside and said management would not reward me for my efforts, but will get the benefit of all my work.
He was right.
Eventually, I left because I automate things to make my life easier. If it's not making my life easier (or getting me more money), why should I do it?
Since then, whenever I get a new job, I test the waters. If the outcome is like that first job, I stop working on process improvements, and look for another job.