When somebody publishes a bullshit paper that is eventually withdrawn, every subsequent paper citing the fraudulent work can also be withdrawn as being unreliable.

It depends on how foundational it is, of course. If you could swap it for a dozen other papers, nobody cares. If you're continuing the work from a retracted paper, you're fucked (but then, you probably would have noticed some errors pretty soon anyway).

I have a friend who basically ran a series of experiments based on a paper that was complete bullshit. And like any good biochemist, he figured he was screwing up, or the equipment was faulty, or the substrate was more cursed than usual. Lucky for him, after weeks of smashing into a brick wall of failure, he started asking other people, who also kept failing and then they figured it out.