Criticisms of TSM

I have been looking into TSM — their gross margin, net margin, and other fundamentals — and watched a few videos on their importance such as how they make up the 'silicon shield' of Taiwan. All of this puts them to be a good company. Even so, because all the things that I hear or read about them is positive and rarely any negative, I was wondering: What are some negatives of TSM? Where do they lack? And to those of you who know about TSM but have not bought: Why? — What is your reason? Thank You.