I'm having discussion about this with my friend and we are both doing SEO. Lately we discuss about what triggers site for manual review. According to him there is a list of niches that are manually checked by google employees. I mean niches that are sensitive, like payday loans, some weight loss, pills, hacks, forex, binary etc etc. My opinion on this is that niche doesn't matter. Like If you have insane amount of traffic, but your SEO technique is a little bit dark you will still get caught, even if you write about cute dogs and cats. I would like to know other peoples opinion on this, also if you have some experience you can kindly share...Tnx a lot guys.