Why are Tax Liens and Tax Deeds documented evil on this website

[Ashish D.]

I've read through hundreds of post on this website about Tax Liens and Tax Deeds, and almost every single one is discouraging investing into it stating myriad of different problems and nuances. However, when you search the internet, you find hundreds of posts and documentation talking about investors being so successful with it, big ones and small. I've spoken to few investors who have made tens of properties using it. Why are posts and documentation on this website particularly advising against them?