Defining "really good table tennis"

What is really good table tennis?

There's a stall at my local hawker centre that sells really good peanut porridge with fishcake (soft & fried), chicken wings and omelets. The stall owners - a couple - cook these five items really well. Consistently nice taste, no hint of poor taste or sogginess. They may not have won any major culinary award, but their experienced and precise methods for preparing these 5 items is enough for patrons like me to keep coming back, sometimes forming long queues. 

Really good table tennis is like that - it's not so much the ability to execute moves worthy of showing up at the Olympics or TT World Cup finals, but the absence of poor / soggy moves. Good TT is often characterized more by the absence of clumsiness and blundering choices than by the profusion of high-speed smashes that captivate the audience. Of course those will happen too, but they are opportunistic, not key staple. And the two (or four) players involved may only have five winning moves between them but that's enough variety to keep the audience entertained because the process of getting to those moves is ever new.

To achieve good table tennis, one must be aware that it's a game of minute differences. Especially in terms of spatial awareness (or depth perception) and force sensitivity (or precise energy transfer). A young player I encountered recently for the first time across the table immediately discerned that there was something off about my racket, and sure enough there was - a secondhand backhand rubber was cut to a smaller size by something like half a centimetre at its bottom corners - and he cannot help but notice it. 

Given the importance of depth perception, one has to possess perfect vision to play really good table tennis. As for the precision of energy transfer, it's best to have training partner(s) with whom on the basis of good energy transfer you can practice generating greater and greater force, ball speed and spin. A player must be constantly challenged by people other than his familiar partner(s) in order to overcome weaknesses and blindspots that happen to be convergent with said familiar partner(s). Such practice and challenges will no doubt eventually lead one to be able to play really good table tennis.