What is your definition of a "hack" or "hack job"?
Everyone's definitions will be different.
Here are things I consider indicative of a "hack job" relative to this subject (no particular order):
1. Patching new electrolytics across existing ones without removing the existing part electrically.
2. Bridging a wire to a terminal with solder in cases where the wire is too short.
3. Shoddy soldering that looks like someone tried to paint on the solder.
4. Use of a capacitor with a voltage rating at or below the normal operating voltage in-circuit.
5. User of a resistor with a power rating that is not at least 2 times the expected dissipation in the circuit.
6. Flying wire splices without insulation.
7. Multiple components joined in mid-air without a terminal (unless that was the way the radio was designed to be assembled - yeah they sometimes did stupid stuff back then).
8. Failure to install adequate safety items even if they are not "original." The house you burn down may be your own, or worse yet someone else's.
9. Use of improper insulation for spliced wiring connections (e.g. masking tape, transparent tape).
10. Mis-routing high impedance high-gain signal wires. This can mean routing them too close to filament or AC power wires, or even just pulling them up away from the chassis in a way that makes them more susceptible to hum pick-up.
11. Installing components with seriously wrong values (order of magnitude errors in component replacement).
12. Installing "susbstitue" tubes that really are not adequately equivalent (like remote versus sharp cut-off tubes).
13. Leaving out shielding that is supposed to be present (generally tube shields).
14. Creating a wire splice by just twisting wires together then insulating it so no one knows that it isn't soldered without cutting off the insulation. The exception would be the use of standard wire nuts where this is expected.
This could be never ending, but I'll stop.
Thanks a lot Curtis, I now have 14 things i can,t do any more. It will now take me much longer to restore a radio