Seikosha gave a good answer. Any influence to the diamond will give a result you can hear. Normally there is a shift of the reproduced frequencies (more bass, smooth highs...) and some like that and write what "sound" their turntable has. A good turntable has no sound. It is a neutral medium, the better it is, the more information you will get from your records, no matter what music is played. Analog is a mechanical reproduction, it is based on science, material knowledge and precision. When done right, it can't be cheap. Unfortunately you have no guarantee that you will get a top product for your money because all Designers are perfect :-)
This creates of course some frustration and that is the reason for some to look for yesteryear designs in the hope they will get a serious product for small money. Sometimes it works but most is not worth to talk about.
Rim / Idler drive was a technology when nothing else was available and the only advantage was the acceleration from scratch (important for Radio Stations who were not interested in a wide frequency area we want to have from High End units). All those rumbling devices were replaced as soon as possible with Direct Drives when they became available. they can hold the speed for they have always corrections while spinning (in a good System you can hear it easily when you know what is going on). High End is running in circles, a few years one Design is hip, after some years that Design will follow and so on. And behind everything is the need to make money. So it is normal that you will find more and more refurbished items which were bought for $250,-- and after some wood work and replacing a few parts it is offered for $10k.
It works. But Physics is Physics. Normally you can't change it. The only exception is High End.