Kind of an extreme example, but it illustrates the point well: that one forgotten employee from the infamous reddit thread[0] who got hired, the company had a mismanagement shitshow, and he eventually ended up having no manager and no assignments/work for months. He realized they just forgot about him and continued showing up to work to just play games and relax by himself, all while collecting the paycheck for over a year. IIRC he mentioned enjoying this, but worrying about what could happen if they “unforget” about him. That situation was a classic example of a dead-end job, even though OP was having a good time at first.
P.S. The original threat wasn’t the most popular one, but the follow up to it with how he eventually got found out (about a year after the original post) was massive[1].
If you love your job, you wouldn't want to go anywhere else or "progress" in your career. BTW, what is that "progress" in a career? Endless better pay? Longer job title? More work? More difficult work? Switch to management (that's a different career to me)?
The example is not relevant. That's not a dead-end job. If there's no work, then that's no longer a job at all.
A job would look like a dead-end only if you hate it.