I don't say anyone else is wrong, but there is probably a definitive answer to this. The problem is that we are all subject to bias from what we upgraded last and which last impinged on our appreciation of our music. I'm just as subject to that as anyone else, so take this with a grain of salt.
1. Cartridge
2. Phono stage
3. Tonearm
4. Turntable.
And to qualify, if any one of the above is letting down the rest, it should automatically move to the top of the list for immediate replacement.