When your dating profiles don't match! The bacteriophage (that spider-looking virus with the geometric head) is specialized to inject its DNA into bacteria, but here it's getting rejected by an animal cell that's basically saying "wrong port, buddy!"
It's like showing up to a USB-C party with your old-school VGA connector. Bacteriophages have these amazing lock-and-key mechanisms to dock onto bacterial cells, but animal cells? Completely different security system! The poor phage is getting the cellular equivalent of "new phone, who dis?"